JP2018148074A - Light-emitting element and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide light-emitting elements suitable for a narrow-pitch light-emitting element array, in which a plurality of light-emitting parts different in emission wavelength are formed in one light-emitting element.SOLUTION: A light-emitting element comprises: a window layer doubling a support substrate; and a plurality of light-emitting parts provided on the window layer doubling the support substrate, and differing from each other in emission wavelength. The plurality of light-emitting parts each have a structure in which a second semiconductor layer of a second conductivity type, an active layer, and a first semiconductor layer of a first conductivity type are formed in this order, have a removed portion where the first or second semiconductor layer and the active layer are removed, and a non-removed portion other than the removed portion, and further have a first ohmic electrode provided on the non-removed portion, and a second ohmic electrode provided on the removed portion.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light emitting device and a method for manufacturing the same.

  In AR (Augmented Reality) and HMD (Head Mounted Display), an ultra-compact display having a long side of about 1 to 2 cm □ is essential and a display with high brightness is required.

  When a full HD standard display with a long side of about 1 to 2 cm □ is required, a pixel of 1920 × 1080 pixels is required, so the size of one pixel is realized with a pitch of about 5.2 μm to 10.4 μm □. There is a need.

  In such an ultra-small light emitter, high luminance is required per unit area of one element, and a self-luminous light-emitting element is more ideal than an LCD such as Patent Document 1 or an organic EL display such as Patent Document 2. Is.

  In addition, since high process accuracy is required, it is appropriate to select a material applicable to the semiconductor process.

JP 2013-210588 A JP2013-037021A

  The monochrome display with the pixel size as described above can be realized by using a wafer to which a semiconductor process can be applied, as disclosed in CEA-LETI (France).

  However, the technology disclosed in CEA-LETI is monochromatic, and there is no proposal for a multicolor technology. This is because, in an InGaN-based epitaxial wafer that realizes blue-green light emission and an AlGaInP-based material that realizes yellow-red light emission, the optimum temperature range for forming the wafer (800-1000 ° C. for InGaN system, 500-700 ° C. for AlGaInP system) ) And a substrate (a sapphire substrate in an InGaN system, and a GaAs substrate in an AlGaInP system) are very difficult to form simultaneously on a wafer by a technique such as epitaxial growth.

  Although it is technically possible to realize a display by dicing a very small light emitting element and transferring it to a driving substrate, for example, when trying to realize two-color light emission in a 1920 × 1080 pixel display If it is transferred at a rate of 0.2 seconds / piece, it takes about 240 days of production time, which is not realistic.

  In order to realize a light emitting element array with a narrow pitch (small size) with high density, a wafer having a function of different emission wavelengths on one wafer is realized, a device array with a narrow pitch is manufactured by a semiconductor process, and a display is formed. It is desirable to realize.

  The present invention has been made in view of the above problems, and a plurality of light-emitting portions having different emission wavelengths are formed in one light-emitting element, and a light-emitting element suitable for a light-emitting element array having a narrow pitch and the manufacture of such a light-emitting element. It aims to provide a method.

  In order to achieve the above object, in the present invention, a light emitting device comprising a window layer / support substrate and a plurality of light emitting portions having different emission wavelengths provided on the window layer / support substrate, Each of the light emitting portions has a structure in which a second conductive type second semiconductor layer, an active layer, and a first conductive type first semiconductor layer are formed in this order, and the first semiconductor layer or the first conductive layer A removed portion from which the two semiconductor layers and the active layer have been removed; a non-removed portion other than the removed portion; and a first ohmic electrode provided in the non-removed portion; and provided in the removed portion There is provided a light emitting device having the second ohmic electrode formed.

  With such a light emitting element, a plurality of light emitting portions having different emission wavelengths are formed in one light emitting element, and the light emitting element is suitable for a light emitting element array with a narrow pitch.

  In addition, one of the plurality of light emitting units is composed of an epitaxial layer directly formed on the window layer / supporting substrate, and the other light emitting unit is bonded onto the epitaxial layer. It is preferable.

  With such a light emitting element, light having a plurality of wavelengths can be emitted to the outside while maintaining high luminance without causing interference with each other.

Further, between the light emitting portion joined onto the epitaxial layer and the window layer and the support epitaxial layer formed directly on the substrate, it is preferable that the have a benzocyclobutene film or SiO ₂ film.

  With such a light emitting element, the junction between the epitaxial layer directly formed on the window layer / supporting substrate and the light emitting portion joined on the epitaxial layer becomes mechanically stronger.

  The plurality of light emitting portions may include a light emitting portion made of a blue-green InGaN-based material and a light emitting portion made of a red-yellow AlGaInP-based material.

  Thus, if it is a light emitting element of this invention, it can be set as the light emitting element provided with the several light emission part from which light emission wavelengths differ, such as a blue-green type and a red yellow type, for example.

  According to the present invention, there is also provided a method for manufacturing a light-emitting element, comprising: a first epitaxial substrate on which an epitaxial layer that emits light of a first wavelength is grown on a first substrate; and a second substrate. A step of preparing a second epitaxial substrate on which an epitaxial layer that emits light of the second wavelength is grown is bonded to the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate. There is provided a method for manufacturing a light-emitting element, which includes a step and a step of removing the first substrate or the second substrate from the bonded epitaxial substrate.

  With such a manufacturing method, since light emitting portions having two or more types of light emission wavelengths are separately formed and then joined, each can be grown under optimum crystal growth conditions. A highly efficient light emitting layer (light emitting element region) can be obtained. Accordingly, it is possible to easily manufacture a light emitting element that includes a plurality of light emitting units having different emission wavelengths and can emit light to the outside while maintaining high luminance without causing light of a plurality of wavelengths to interfere with each other.

  The epitaxial layer that emits light of the first wavelength can be an InGaN-based material, and the epitaxial layer that emits light of the second wavelength can be an AlGaInP-based material.

  As described above, according to the manufacturing method of the present invention, a light-emitting element including a plurality of light-emitting portions having different emission wavelengths such as blue-green and red-yellow can be easily manufactured.

  The second conductive type second semiconductor layer, the active layer, and the first conductive type first epitaxial layer that emits light of the first wavelength and the epitaxial layer that emits light of the second wavelength It is preferable to form an epitaxial layer having a structure in which the semiconductor layers are formed in this order.

  Thus, the manufacturing method of the present invention is suitable for a method of forming a light emitting part having a double hetero structure.

  In each of the epitaxial layer that emits light of the first wavelength and the epitaxial layer that emits light of the second wavelength after the step of removing the first substrate or the second substrate, A removed portion from which the first semiconductor layer or the second semiconductor layer and the active layer are removed and a non-removed portion other than the removed portion are formed, a first ohmic electrode is provided in the non-removed portion, and the removed portion is provided. It is preferable to have the process of providing a 2nd ohmic electrode.

  If it is the manufacturing method of this invention, an ohmic electrode can be provided in a light emission part by such a process.

  Further, before the step of bonding the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate, the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate are bonded. Preferably, a benzocyclobutene film is formed on at least one, and then the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate are bonded together via the benzocyclobutene film.

Further, before the step of bonding the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate, the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate are bonded. Preferably, an SiO ₂ film is formed on at least one of the layers, and then the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate are bonded together via the SiO ₂ film.

By bonding the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate through the benzocyclobutene film or the SiO ₂ film in this way, the bonding between the epitaxial layers is more mechanically strong. Can be.

  As described above, in the light-emitting element of the present invention, a plurality of light-emitting portions having different emission wavelengths are formed in one light-emitting element, for example, two or more colors of blue to green and yellow to red A light-emitting element that can display and can emit light to the outside while maintaining high luminance without interfering light of a plurality of wavelengths with each other. Therefore, the light emitting device of the present invention is particularly suitable for a light emitting device array with a narrow pitch. Further, according to the method for manufacturing a light emitting element of the present invention, since light emitting portions having two types of light emission wavelengths are separately formed and then joined, each can be grown under optimum crystal growth conditions. A light-emitting layer (light-emitting element region) that is highly efficient with respect to the wavelength can be obtained. Accordingly, a light-emitting element suitable for a light-emitting element array having a narrow pitch and having a plurality of light-emitting portions having different emission wavelengths and capable of radiating to the outside while maintaining high luminance without causing light of a plurality of wavelengths to interfere with each other Can be easily manufactured.

It is the schematic which shows 1st embodiment of the manufacturing method of the light emitting element of this invention. It is the schematic which shows 2nd embodiment of the manufacturing method of the light emitting element of this invention. It is the schematic which shows 3rd embodiment of the manufacturing method of the light emitting element of this invention. It is the schematic which shows 4th embodiment of the manufacturing method of the light emitting element of this invention. It is the schematic which shows 5th embodiment of the manufacturing method of the light emitting element of this invention. It is the schematic which shows 6th embodiment of the manufacturing method of the light emitting element of this invention. It is the schematic which shows an example of the wiring board which mounts the light emitting element of this invention. It is the schematic which shows another example of the wiring board which mounts the light emitting element of this invention. It is the schematic which shows an example of the light emitting element of this invention mounted in the wiring board.

  As described above, a plurality of light emitting portions having different emission wavelengths are formed in one light emitting element, and there has been a demand for development of a light emitting element suitable for a light emitting element array with a narrow pitch and a method for manufacturing such a light emitting element.

  As a result of intensive studies on the above-mentioned problems, the present inventors can grow each of them under optimum crystal growth conditions as long as the light-emitting portions having two types of emission wavelengths are separately formed and then joined. Therefore, it was found that a light-emitting element in which a plurality of light-emitting portions having different emission wavelengths are formed in one light-emitting element can be easily manufactured, and the present invention has been completed.

  That is, the present invention is a light emitting device comprising a window layer / support substrate and a plurality of light emitting portions with different emission wavelengths provided on the window layer / support substrate, wherein the plurality of light emitting portions are all The second conductivity type second semiconductor layer, the active layer, and the first conductivity type first semiconductor layer have a structure formed in this order, and the first semiconductor layer or the second semiconductor layer and the active A first ohmic electrode provided on the non-removable portion, and a second ohmic electrode provided on the removed portion. It is a light emitting element which has these.

  Hereinafter, although the present invention is explained in detail, referring to drawings, the present invention is not limited to these.

(First embodiment)
A first embodiment of a light emitting device of the present invention will be described with reference to FIG. As shown in FIG. 1 (h), the light emitting device 12 in the first embodiment of the present invention includes a sapphire substrate 155 which is a window layer and supporting substrate, and a blue-green InGaN system provided on the sapphire substrate 155. A light-emitting element including a light-emitting portion made of a material and a light-emitting portion made of a red-yellow AlGaInP-based material.

The light emitting portion made of a blue-green InGaN material includes an N-type cladding layer (second semiconductor layer) 151 made of Al _s Ga _1-s N (0 ≦ s ≦ 1), In _s Ga _1-s N (0 ≦ s ≦ 1) and a P-type cladding layer (first semiconductor layer) 153 made of Al _s Ga _1-s N (0 ≦ s ≦ 1) are formed in this order. The P-type cladding layer 153 and the active layer 152 are removed, and a non-removable portion 160 other than the removed portion 170 is provided. It has a third electrode (first ohmic electrode) 161 that is in contact, and a fourth electrode (second ohmic electrode) 171 that is provided in the removal portion 170 and is in contact with the N-type cladding layer 151.

The light emitting portion made of a red-yellow AlGaInP material is a P-type cladding layer made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6). (First semiconductor layer) 103, active layer 102 made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6), and (Al _x Ga) _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) and an N-type cladding layer (second semiconductor layer) 101 are formed in this order. The N-type cladding layer 101 and the active layer 102 are removed, and a non-removable portion 110 other than the removed portion 120 is provided. A first electrode (first ohmic electrode) 111 in contact with the P-type cladding layer, and a P-type cladding layer 03 and in contact with that second electrode and a (second ohmic electrode) 121. The light emitting portion made of a red-yellow AlGaInP-based material is bonded on an epitaxial layer made of a blue-green InGaN-based material.

  Both of the two light emitting portions are covered with an insulating layer 115, and a bump 140 is formed on the first electrode 111, the second electrode 121, the third electrode 161, and the fourth electrode 171. Yes.

Next, the manufacturing method of the light emitting element in 1st embodiment of this invention is demonstrated with reference to Fig.1 (a)-(h). First, as shown in FIG. 1 (a), an N type made of Al _s Ga _1-s N (0 ≦ s ≦ 1) is formed on a sapphire substrate 155 by, for example, metal organic vapor phase epitaxy (MOVPE). cladding layer (second semiconductor _{layer) 151, In s Ga 1-} s N (0 ≦ s ≦ 1) active layer _{152, Al s Ga 1-s} N (0 ≦ s ≦ 1) P -type cladding layer consisting of consisting of By sequentially laminating (first semiconductor layer) 153, an InGaN-based epitaxial wafer 150 which is a blue / green light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method.

Further, as shown in FIG. 1B, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x) is formed on the GaAs substrate 105 by, eg, metal organic vapor phase epitaxy (MOVPE). ≦ 1, 0.4 ≦ y ≦ 0.6) N-type cladding layer (second semiconductor layer) 101, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1,0,. Active layer 102 composed of 4 ≦ y ≦ 0.6), P-type cladding composed of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) By sequentially laminating the layers (first semiconductor layers) 103, the AlGaInP-based epitaxial wafer 100 that is a red / yellow light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method.

  Next, as shown in FIG. 1C, an InGaN-based epitaxial wafer 150 and an AlGaInP-based epitaxial wafer 100 are bonded. At this time, both the AlGaInP epitaxial wafer 100 and the InGaN epitaxial wafer 150 are immersed in an alkaline solution (KOH aqueous solution or NaOH aqueous solution) to alkali-treat the surface, and the epitaxial surfaces of the AlGaInP epitaxial wafer 100 and the InGaN epitaxial wafer 150 are treated. The two wafers were bonded together by bringing them into contact with each other (P-type cladding layer 103 and P-type cladding layer 153) in a vacuum, pressing them together at a pressure of 500 N or higher, and holding them at a temperature of 500 ° C. or higher. The bonded wafer 10 can be formed.

  Before bonding, the thickness of the GaAs substrate of the AlGaInP-based epitaxial wafer 100 may be processed to a thickness of about 50 to 100 μm by etching or grinding. By thin film processing, the AlGaInP-based epitaxial wafer 100 is easily deformed during bonding, and there is an effect of increasing the yield after bonding.

  Next, as shown in FIG. 1D, a wafer 11 is formed by removing the GaAs substrate 105 of the AlGaInP epitaxial wafer 100 by chemical etching. The chemical etchant preferably has an etching selectivity with respect to the AlGaInP-based material, and is generally removed with an ammonia-containing etchant. In this case, the substrate to be processed or removed may be a sapphire substrate 155.

  Next, as shown in FIG. 1E, a part of the N-type clad layer 101 and the active layer 102 is removed from the epitaxial layer made of an AlGaInP-based material, thereby forming a removal part 120 and a non-removal part 110. . The removal at this time can be performed by etching with the non-removal part 110 as a mask, for example. Then, a first electrode (first ohmic electrode) 111 is formed on the N-type cladding layer 101 (non-removed portion 110) of the AlGaInP-based epitaxial wafer 100, and a part of the N-type cladding layer 101 and the active layer 102 is cut away. A second electrode (second ohmic electrode) 121 is formed in a part of the removed region (removal part) 120.

Next, as shown in FIGS. 1F and 1G, in the region 130 where the first electrode 111 and the second electrode 121 of the epitaxial layer made of InGaN-based material are not formed, the P-type cladding layer 153 and the active layer are activated. A part of the layer 152 is removed to form a removal part 170 and a non-removal part 160. The removal at this time is performed by, for example, an ICP etching method in an atmosphere containing a Cl-based gas (Cl ₂ , BCl ₃ , SiCl ₄ ) while masking the non-removed portion 160 and the light emitting portion made of an AlGaInP-based material. it can.

  Next, as shown in FIG. 1G, a third electrode (first ohmic electrode) 161 is formed on a part (non-removed portion 160) of the P-type cladding layer 153 of the exposed InGaN-based epitaxial wafer 150, A fourth electrode (second ohmic electrode) 171 is formed in a part of the region (removal part) 170 in which a part of the P-type cladding layer 153 and the active layer 152 is cut out.

  Next, as shown in FIG. 1 (h), bumps 140 are formed on the first electrode 111, the second electrode 121, the third electrode 161, and the fourth electrode 171 to produce the light emitting wafer (light emitting element) 12. To do. Note that the bumps may be formed of studs or plated.

(Second embodiment)
A second embodiment of the light emitting device of the present invention will be described with reference to FIG. As shown in FIG. 2H, the light-emitting element 22 in the second embodiment of the present invention includes a sapphire substrate 255 that is a window layer and supporting substrate, and a blue-green InGaN system provided on the sapphire substrate 255. A light-emitting element including a light-emitting portion made of a material and a light-emitting portion made of a red-yellow AlGaInP-based material.

The light emitting portion made of a blue-green InGaN material includes an N-type cladding layer (second semiconductor layer) 251 made of Al _s Ga _1-s N (0 ≦ s ≦ 1), In _s Ga _1-s N (0 ≦ s ≦ 1) and a P-type cladding layer (first semiconductor layer) 253 made of Al _s Ga _1-s N (0 ≦ s ≦ 1) are formed in this order. The P-type cladding layer 253 and the active layer 252 are removed, and a non-removable portion 260 other than the removed portion 270 is provided. It has a third electrode (first ohmic electrode) 261 that is in contact, and a fourth electrode (second ohmic electrode) 271 that is provided in the removal portion 270 and is in contact with the second semiconductor layer 251.

The light emitting portion made of a red-yellow AlGaInP material is a P-type cladding layer made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6). (First semiconductor layer) 203, active layer 202 made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6), and (Al _x Ga) _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) and an N-type cladding layer (second semiconductor layer) 201 formed in this order. The N-type cladding layer 201 and the active layer 202 are removed, and a non-removal portion 210 other than the removal portion 220 is provided. A first electrode (first ohmic electrode) 211 in contact with the P-type cladding layer 03 and in contact with that second electrode and a (second ohmic electrode) 221. The light emitting portion made of a red-yellow AlGaInP-based material is bonded via an benzocyclobutene film 204 on an epitaxial layer made of a blue-green InGaN-based material.

  Each of the two light emitting portions is covered with an insulating layer 215, and a bump 240 is formed on the first electrode 211, the second electrode 221, the third electrode 261, and the fourth electrode 271. Yes.

Next, the manufacturing method of the light emitting element in 2nd embodiment of this invention is demonstrated with reference to Fig.2 (a)-(h). First, as shown in FIG. 2 (a), an N type made of Al _s Ga _1-s N (0 ≦ s ≦ 1) is formed on a sapphire substrate 255 by, for example, metal organic vapor phase epitaxy (MOVPE). cladding layer (second semiconductor _{layer) 251, In s Ga 1-} s N (0 ≦ s ≦ 1) active layer _{252, Al s Ga 1-s} N (0 ≦ s ≦ 1) P -type cladding layer consisting of consisting of By sequentially laminating (first semiconductor layer) 253, an InGaN-based epitaxial wafer 250 that is a blue / green light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method.

As shown in FIG. 2B, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x) is formed on the GaAs substrate 205 by, eg, metal organic chemical vapor deposition (MOVPE). ≦ 1, 0.4 ≦ y ≦ 0.6) N-type cladding layer (second semiconductor layer) 201, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1,0,. Active layer 202 made of 4 ≦ y ≦ 0.6), P-type cladding made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) By sequentially laminating layers (first semiconductor layers) 203, an AlGaInP-based epitaxial wafer 200, which is a red / yellow light emitting material, is produced. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method.

  Next, benzocyclobutene (BCB) is applied to the epitaxial surface (on the P-type cladding layer 203) of the AlGaInP-based epitaxial wafer 200 at a rotation speed of 3,000 rpm or more, and a BCB film 204 having a thickness of about 1 μm is formed. Form. Then, as shown in FIG. 2 (c), the BCB coated surface of the AlGaInP-based epitaxial wafer 200 is brought into contact with the epitaxial surface (P-type cladding layer 253) of the InGaN-based epitaxial wafer 250 at a pressure of 500 N or more. By bonding both of them and maintaining the temperature at 150 ° C. or higher, a bonded wafer 20 in which both wafers are bonded can be formed. Note that the BCB film may be formed on only one of the first epitaxial substrate and the second epitaxial substrate, or on both.

  Further, before bonding, the thickness of the GaAs substrate of the AlGaInP-based epitaxial wafer 200 may be processed to a thickness of about 50 to 100 μm by etching or grinding. By thin film processing, the AlGaInP-based epitaxial wafer 200 is easily deformed during bonding, and there is an effect of increasing the yield after bonding.

  Next, as shown in FIG. 2D, a wafer 21 is formed by removing the GaAs substrate 205 of the AlGaInP epitaxial wafer 200 by chemical etching. The chemical etchant preferably has an etching selectivity with respect to the AlGaInP-based material, and is generally removed with an ammonia-containing etchant. In this case, the substrate to be processed or removed may be a sapphire substrate 255.

  Next, as shown in FIG. 2E, in the epitaxial layer made of an AlGaInP-based material, a part of the N-type cladding layer 201 and the active layer 202 is removed to form a removal part 220 and a non-removal part 210. . The removal at this time can be performed by etching with the non-removal part 210 as a mask, for example. Then, a first electrode (first ohmic electrode) 211 is formed on the N-type cladding layer 201 (non-removed portion 210) of the AlGaInP-based epitaxial wafer 200, and a part of the N-type cladding layer 201 and the active layer 202 is cut away. A second electrode (second ohmic electrode) 221 is formed in part of the region (removal portion) 220 that has been removed.

Next, as shown in FIGS. 2F and 2G, in the region 230 where the first electrode 211 and the second electrode 221 of the epitaxial layer made of InGaN-based material are not formed, the F-based gas (CF ₄ , The BCB film 204 is removed by ICP etching in an atmosphere containing CHF ₃ , C ₂ F ₆ , C ₃ F ₈ , NF ₃ , SF ₄ , SF ₆ ), and the surface of the InGaN-based epitaxial wafer (P-type cladding) Layer 253) is exposed. Then, a part of the P-type cladding layer 253 and the active layer 252 is removed to form a removal part 270 and a non-removal part 260. The removal at this time is performed by, for example, an ICP etching method in an atmosphere containing a Cl-based gas (Cl ₂ , BCl ₃ , SiCl ₄ ) while masking the non-removed portion 260 and the light emitting portion made of an AlGaInP-based material. it can.

  Next, as shown in FIG. 2G, a third electrode (first ohmic electrode) 261 is formed on a part (non-removed portion 260) of the P-type cladding layer 253 of the exposed InGaN-based epitaxial wafer 250, A fourth electrode (second ohmic electrode) 271 is formed in a part of the region (removal part) 270 where a part of the P-type cladding layer 253 and the active layer 252 is cut out.

  Next, as shown in FIG. 2 (h), bumps 240 are formed on the first electrode 211, the second electrode 221, the third electrode 261, and the fourth electrode 271 to produce the light emitting wafer (light emitting element) 22. To do. Note that the bumps may be formed of studs or plated.

(Third embodiment)
A third embodiment of the light emitting device of the present invention will be described with reference to FIG. As shown in FIG. 3 (h), the light emitting device 32 in the third embodiment of the present invention includes a sapphire substrate 355 that is a window layer and supporting substrate, and a blue-green InGaN system provided on the sapphire substrate 355. A light-emitting element including a light-emitting portion made of a material and a light-emitting portion made of a red-yellow AlGaInP-based material.

The light emitting portion made of a blue-green InGaN material includes an N-type cladding layer (second semiconductor layer) 351 made of Al _s Ga _1-s N (0 ≦ s ≦ 1), In _s Ga _1-s N (0 ≦ s ≦ 1) and a P-type cladding layer (first semiconductor layer) 353 made of Al _s Ga _1-s N (0 ≦ s ≦ 1) are formed in this order. The P-type cladding layer 353 and the active layer 352 are removed, and a non-removal portion 360 other than the removal portion 370 is provided. The non-removal portion 360 is further provided with a P-type cladding layer 353. It has a third electrode (first ohmic electrode) 361 that is in contact, and a fourth electrode (second ohmic electrode) 371 that is provided in the removal portion 370 and is in contact with the N-type cladding layer 351.

The light emitting portion made of a red-yellow AlGaInP material is a P-type cladding layer made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6). (First semiconductor layer) 303, active layer 302 made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6), and (Al _x Ga) _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) and an N-type cladding layer (second semiconductor layer) 301 are formed in this order. The N-type cladding layer 301 and the active layer 302 are removed, and a non-removal portion 310 other than the removal portion 320 is provided. A first electrode (first ohmic electrode) 311 in contact with the P-type cladding layer 03 and in contact with that second electrode and a (second ohmic electrode) 321. The light emitting portion made of a red-yellow AlGaInP-based material is bonded to the epitaxial layer made of a blue-green InGaN-based material via _two SiO ₂ films 306 and 356.

  Each of the two light emitting portions is covered with an insulating layer 315, and a bump 340 is formed on the first electrode 311, the second electrode 321, the third electrode 361, and the fourth electrode 371. Yes.

Next, the manufacturing method of the light emitting element in 3rd embodiment of this invention is demonstrated with reference to Fig.3 (a)-(h). First, as shown in FIG. 3 (a), an N type made of Al _s Ga _1-s N (0 ≦ s ≦ 1) is formed on a sapphire substrate 355 by, for example, metal organic vapor phase epitaxy (MOVPE). cladding layer (second semiconductor _{layer) 351, In s Ga 1-} s N (0 ≦ s ≦ 1) active layer _{352, Al s Ga 1-s} N (0 ≦ s ≦ 1) P -type cladding layer consisting of consisting of By sequentially laminating (first semiconductor layer) 353, an InGaN-based epitaxial wafer 350 that is a blue / green light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method. Then, an SiO ₂ film 356 is formed on the P-type cladding layer 353.

As shown in FIG. 3B, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x) is formed on the GaAs substrate 305 by, eg, metal organic vapor phase epitaxy (MOVPE). ≦ 1, 0.4 ≦ y ≦ 0.6) N-type cladding layer (second semiconductor layer) 301, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1,0,. 4 ≦ y ≦ 0.6) active layer 302, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) P-type cladding By sequentially laminating layers (first semiconductor layers) 303, an AlGaInP-based epitaxial wafer 300 that is a red / yellow light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method. Then, an SiO ₂ film 306 is formed on the P-type cladding layer 303. The SiO ₂ film may be formed on only one of the first epitaxial substrate and the second epitaxial substrate, or may be formed on both.

Next, as shown in FIG. 3C, the InGaN epitaxial wafer 350 and the AlGaInP epitaxial wafer 300 are bonded. At this time, both the AlGaInP-based epitaxial wafer 300 and the InGaN-based epitaxial wafer 350 are immersed in an alkaline solution (KOH aqueous solution or NaOH aqueous solution) to alkali-treat the surface, and the SiO _{2 of the} AlGaInP-based epitaxial wafer 300 and the InGaN-based epitaxial wafer 350 is treated. By bringing the films into contact with each other in a vacuum, pressure-bonding them with a pressure of 500 N or higher, and holding them at a temperature of 700 ° C. or higher, it is possible to form a bonded wafer 30 in which both wafers are bonded.

  Next, as shown in FIG. 3D, a wafer 31 is formed by removing the GaAs substrate 305 of the AlGaInP epitaxial wafer 300 by chemical etching. The chemical etchant preferably has an etching selectivity with respect to the AlGaInP-based material, and is generally removed with an ammonia-containing etchant. In this case, the substrate to be processed or removed may be a sapphire substrate 355.

  Next, as shown in FIG. 3E, in the epitaxial layer made of an AlGaInP-based material, a part of the N-type cladding layer 301 and the active layer 302 is removed to form a removal portion 320 and a non-removal portion 310. . The removal at this time can be performed, for example, by etching with the non-removal portion 310 masked. Then, a first electrode (first ohmic electrode) 311 is formed on the N-type cladding layer 301 (non-removed portion 310) of the AlGaInP-based epitaxial wafer 300, and a part of the N-type cladding layer 301 and the active layer 302 is cut away. A second electrode (second ohmic electrode) 321 is formed in part of the region (removal part) 320 that has been removed.

Next, as shown in FIGS. 3F and 3G, in the region 330 where the first electrode 311 and the second electrode 321 of the epitaxial layer made of the InGaN-based material are not formed, the F-based gas (CF ₄ , The SiO ₂ films 306 and 356 are removed by an ICP etching method in an atmosphere containing CHF ₃ , C ₂ F ₆ , C ₃ F ₈ , NF ₃ , SF ₄ , SF ₆ ), and the surface of the InGaN-based epitaxial wafer ( The P-type cladding layer 353) is exposed. Then, a part of the P-type cladding layer 353 and the active layer 352 is removed to form a removal part 370 and a non-removal part 360. The removal at this time is performed by, for example, an ICP etching method in an atmosphere containing a Cl-based gas (Cl ₂ , BCl ₃ , SiCl ₄ ) while masking the non-removed portion 360 and the light emitting portion made of an AlGaInP-based material. it can.

  Next, as shown in FIG. 3G, a third electrode (first ohmic electrode) 361 is formed on a part (non-removed portion 360) of the P-type cladding layer 353 of the exposed InGaN-based epitaxial wafer 350, A fourth electrode (second ohmic electrode) 371 is formed in a part of a region (removal part) 370 where a part of the P-type cladding layer 353 and the active layer 352 is cut out.

  Next, as shown in FIG. 3H, bumps 340 are formed on the first electrode 311, the second electrode 321, the third electrode 361, and the fourth electrode 371, and the light emitting wafer (light emitting element) 32 is manufactured. To do. Note that the bumps may be formed of studs or plated.

(Fourth embodiment)
A fourth embodiment of the light emitting device of the present invention will be described with reference to FIG. As shown in FIG. 4 (h), the light emitting device 42 according to the fourth embodiment of the present invention includes a sapphire substrate 455 which is a window layer and supporting substrate, and a blue-green InGaN system provided on the sapphire substrate 455. A light-emitting element including a light-emitting portion made of a material and a light-emitting portion made of a red-yellow AlGaInP-based material.

The light emitting portion made of a blue-green InGaN material includes an N-type cladding layer (second semiconductor layer) 451 made of Al _s Ga _1-s N (0 ≦ s ≦ 1), In _s Ga _1-s N (0 ≦ s ≦ 1) and a P-type cladding layer (first semiconductor layer) 453 made of Al _s Ga _1-s N (0 ≦ s ≦ 1) are formed in this order. The P-type cladding layer 453 and the active layer 452 are removed, and a non-removal portion 460 other than the removal portion 470 is provided. It has a third electrode (first ohmic electrode) 461 that is in contact, and a fourth electrode (second ohmic electrode) 471 that is provided in the removal portion 470 and is in contact with the N-type cladding layer 451.

The light emitting portion made of a red-yellow AlGaInP material is a P-type cladding layer made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6). (First semiconductor layer) 403, active layer 402 made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6), and (Al _x Ga) _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) and an N-type cladding layer (second semiconductor layer) 401 are formed in this order. The N-type cladding layer 401 and the active layer 402 are removed, and a non-removal portion 410 other than the removal portion 420 is provided. A first electrode (first ohmic electrode) 411 that is in contact with the P-type clad layer 03 and in contact with that second electrode and a (second ohmic electrode) 421. The light emitting portion made of a red-yellow AlGaInP material is an epitaxial layer (an N-type cladding layer 451, an active layer 452, and a P-type cladding layer 453) that constitutes a light emitting portion made of a blue-green InGaN material. ).

  Each of the two light emitting portions is covered with an insulating layer 415, and a bump 440 is formed on the first electrode 411, the second electrode 421, the third electrode 461, and the fourth electrode 471. Yes.

Next, a method for manufacturing a light-emitting element according to the fourth embodiment of the present invention will be described with reference to FIGS. First, as shown in FIG. 4 (a), an N type made of Al _s Ga _1-s N (0 ≦ s ≦ 1) is formed on a sapphire substrate 455 by, for example, metal organic vapor phase epitaxy (MOVPE). cladding layer (second semiconductor _{layer) 451, In s Ga 1-} s N (0 ≦ s ≦ 1) active layer _{452, Al s Ga 1-s} N (0 ≦ s ≦ 1) P -type cladding layer consisting of consisting of By sequentially laminating (first semiconductor layer) 453, an InGaN-based epitaxial wafer 450 that is a blue / green light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method.

Further, as shown in FIG. 4B, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x) is formed on the GaAs substrate 405 by, for example, metal organic vapor phase epitaxy (MOVPE). ≦ 1, 0.4 ≦ y ≦ 0.6) N-type cladding layer (second semiconductor layer) 401, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1,0,. 4 ≦ y ≦ 0.6) active layer 402, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) P-type cladding By sequentially laminating layers (first semiconductor layers) 403, an AlGaInP-based epitaxial wafer 400 that is a red / yellow light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method.

  Next, as shown in FIG. 4C, the InGaN-based epitaxial wafer 450 and the AlGaInP-based epitaxial wafer 400 are bonded. At this time, both the AlGaInP-based epitaxial wafer 400 and the InGaN-based epitaxial wafer 450 are immersed in an alkaline solution (KOH aqueous solution or NaOH aqueous solution) to treat the surfaces with alkali, and the epitaxial surfaces of the AlGaInP-based epitaxial wafer 400 and the InGaN-based epitaxial wafer 450 are treated. The two wafers were bonded together by bringing them into contact with each other (P-type cladding layer 403 and P-type cladding layer 453) in a vacuum, pressing them together at a pressure of 500 N or higher, and holding them at a temperature of 500 ° C. or higher. A bonded wafer 40 can be formed.

  Further, before bonding, the thickness of the GaAs substrate of the AlGaInP-based epitaxial wafer 400 may be thinned to a thickness of about 50 to 100 μm by etching or grinding. By thin film processing, the AlGaInP-based epitaxial wafer 400 is easily deformed during bonding, and there is an effect of increasing the yield after bonding.

  Next, as shown in FIG. 4D, a wafer 41 is formed by removing the GaAs substrate 405 of the AlGaInP-based epitaxial wafer 400 by chemical etching. The chemical etchant preferably has an etching selectivity with respect to the AlGaInP-based material, and is generally removed with an ammonia-containing etchant. In this case, the substrate to be processed or removed may be a sapphire substrate 455.

  Next, as shown in FIG. 4E, a first electrode (first ohmic electrode) 411 is formed on the N-type cladding layer 401 (non-removed portion 410) of the AlGaInP-based epitaxial wafer 400, and in a region 420 A hole or groove-like shape reaching the P-type cladding layer 403 is formed (that is, the N-type cladding layer 401 and the active layer 402 are removed to provide a removal portion), and the bottom of the region 420 is in contact with the P-type cladding layer 403. Two electrodes (second ohmic electrode) 421 are formed.

Next, as shown in FIG. 4F, a part of the region 430 where the first electrode 411 and the second electrode 421 are not formed is removed from the epitaxial layer made of the AlGaInP-based material. For removing the region 430, an ICP etching method in an atmosphere containing a Cl-based gas (Cl ₂ , BCl ₃ , SiCl ₄ ) is used to expose the surface of the InGaN-based epitaxial wafer (P-type cladding layer 453).

  Next, as shown in FIG. 4G, a third electrode (first ohmic electrode) 461 is formed on a part (non-removed portion 460) of the P-type cladding layer 453 of the exposed InGaN-based epitaxial wafer 450, A hole or groove-like shape reaching the N-type cladding layer 451 is opened in the region 470 (that is, the P-type cladding layer 453 and the active layer 452 are removed to provide a removal portion), and the N-type cladding layer is formed at the bottom of the region 470 A fourth electrode (second ohmic electrode) 471 in contact with 451 is formed.

  Next, as shown in FIG. 4H, bumps 440 are formed on the first electrode 411, the second electrode 421, the third electrode 461, and the fourth electrode 471, and the light emitting wafer (light emitting element) 42 is manufactured. To do. Note that the bumps may be formed of studs or plated.

(Fifth embodiment)
A fifth embodiment of the light emitting device of the present invention will be described with reference to FIG. As shown in FIG. 5 (h), a light emitting device 52 according to the fifth embodiment of the present invention includes a sapphire substrate 555 that is a window layer and supporting substrate, and a blue-green InGaN system provided on the sapphire substrate 555. A light-emitting element including a light-emitting portion made of a material and a light-emitting portion made of a red-yellow AlGaInP-based material.

The light emitting portion made of a blue-green InGaN material includes an N-type cladding layer (second semiconductor layer) 551 made of Al _s Ga _1-s N (0 ≦ s ≦ 1), In _s Ga _1-s N (0 ≦ s ≦ 1) and a P-type cladding layer (first semiconductor layer) 553 made of Al _s Ga _1-s N (0 ≦ s ≦ 1) in this order. The P-type cladding layer 553 and the active layer 552 are removed, and a non-removal portion 560 other than the removal portion 570 is provided. It has a third electrode (first ohmic electrode) 561 that is in contact, and a fourth electrode (second ohmic electrode) 571 that is provided in the removal portion 570 and is in contact with the N-type cladding layer 551.

The light emitting portion made of a red-yellow AlGaInP material is a P-type cladding layer made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6). (First semiconductor layer) 503, active layer 502 made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6), and (Al _x Ga) _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) and an N-type cladding layer (second semiconductor layer) 501 is formed in this order. The N-type cladding layer 501 and the active layer 502 are removed, and a non-removal portion 510 other than the removal portion 520 is provided. The N-type cladding layer 501 is provided in the non-removal portion 510. A first electrode (first ohmic electrode) 511 in contact with the P-type cladding layer 03 and in contact with that second electrode and a (second ohmic electrode) 521. The light emitting portion made of a red-yellow AlGaInP-based material is an epitaxial layer (N-type cladding layer 551, active layer 552, and P-type cladding layer 553) constituting the light-emitting portion made of a blue-green InGaN-based material. ) Through a benzocyclobutene film 504.

  Each of the two light emitting portions is covered with an insulating layer 515, and a bump 540 is formed on the first electrode 511, the second electrode 521, the third electrode 561, and the fourth electrode 571. Yes.

Next, a method for manufacturing a light-emitting element according to the fifth embodiment of the present invention will be described with reference to FIGS. First, as shown in FIG. 5 (a), an N type made of Al _s Ga _1-s N (0 ≦ s ≦ 1) is formed on a sapphire substrate 555 by, for example, metal organic vapor phase epitaxy (MOVPE). cladding layer (second semiconductor _{layer) 551, In s Ga 1-} s N (0 ≦ s ≦ 1) active layer _{552, Al s Ga 1-s} N (0 ≦ s ≦ 1) P -type cladding layer consisting of consisting of By sequentially laminating (first semiconductor layer) 553, an InGaN-based epitaxial wafer 550 that is a blue / green light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method.

Further, as shown in FIG. 5B, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x) is formed on the GaAs substrate 505 by, for example, metal organic vapor phase epitaxy (MOVPE). ≦ 1, 0.4 ≦ y ≦ 0.6) N-type cladding layer (second semiconductor layer) 501, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1,0,. 4 ≦ y ≦ 0.6) active layer 502, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) P-type cladding By sequentially laminating layers (first semiconductor layers) 503, an AlGaInP-based epitaxial wafer 500 that is a red / yellow light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method.

  Next, benzocyclobutene (BCB) is applied to the epitaxial surface (on the P-type cladding layer 503) of the AlGaInP-based epitaxial wafer 500 at a rotation speed of 3,000 rpm or more, and a BCB film 504 having a thickness of about 1 μm is formed. Form. Then, as shown in FIG. 5C, the BCB coated surface of the AlGaInP-based epitaxial wafer 500 is brought into contact with the epitaxial surface (P-type cladding layer 553) of the InGaN-based epitaxial wafer 550 at a pressure of 500 N or more. By bonding both of them and maintaining the temperature at 150 ° C. or higher, a bonded wafer 50 in which both wafers are bonded can be formed. Note that the BCB film may be formed on only one of the first epitaxial substrate and the second epitaxial substrate, or on both.

  Further, before bonding, the thickness of the GaAs substrate of the AlGaInP-based epitaxial wafer 500 may be processed to a thickness of about 50 to 100 μm by etching or grinding. By thin film processing, the AlGaInP-based epitaxial wafer 500 is easily deformed during bonding, and there is an effect of increasing the yield after bonding.

  Next, as shown in FIG. 5D, a wafer 51 is formed by removing the GaAs substrate 505 of the AlGaInP epitaxial wafer 500 by chemical etching. The chemical etchant preferably has an etching selectivity with respect to the AlGaInP-based material, and is generally removed with an ammonia-containing etchant. In this case, the substrate to be processed or removed may be a sapphire substrate 555.

  Next, as shown in FIG. 5E, a first electrode (first ohmic electrode) 511 is formed on the N-type cladding layer 501 (non-removed portion 510) of the AlGaInP-based epitaxial wafer 500, and in a region 520 A hole or groove-like shape reaching the P-type cladding layer 503 is formed (that is, the N-type cladding layer 501 and the active layer 502 are removed to provide a removal portion), and the bottom of the region 520 is in contact with the P-type cladding layer 503. Two electrodes (second ohmic electrode) 521 are formed.

Next, as shown in FIG. 5F, a part of the region 530 where the first electrode 511 and the second electrode 521 are not formed is removed from the epitaxial layer made of the AlGaInP-based material. For removal of the region 530, an ICP etching method in an atmosphere containing a Cl-based gas (Cl ₂ , BCl ₃ , SiCl ₄ ) is used to expose the BCB film 504 on the surface of the InGaN-based epitaxial wafer. Then, the BCB film 504 is removed by ICP etching in an atmosphere containing an F-based gas (CF ₄ , CHF ₃ , C ₂ F ₆ , C ₃ F ₈ , NF ₃ , SF ₄ , SF ₆ ), and the InGaN The surface (P-type cladding layer 553) of the system epitaxial wafer is exposed.

  Next, as shown in FIG. 5G, a third electrode (first ohmic electrode) 561 is formed on a part (non-removed portion 560) of the P-type cladding layer 553 of the exposed InGaN-based epitaxial wafer 550, A hole or groove-like shape reaching the N-type cladding layer 551 is opened in the region 570 (that is, a removal portion is provided by removing the P-type cladding layer 553 and the active layer 552), and the N-type cladding layer is formed at the bottom of the region 570 A fourth electrode (second ohmic electrode) 571 in contact with 551 is formed.

  Next, as shown in FIG. 5 (h), bumps 540 are formed on the first electrode 511, the second electrode 521, the third electrode 561, and the fourth electrode 571, thereby producing a light emitting wafer (light emitting element) 52. To do. Note that the bumps may be formed of studs or plated.

(Sixth embodiment)
A sixth embodiment of the light emitting device of the present invention will be described with reference to FIG. As shown in FIG. 6 (h), the light emitting device 62 in the sixth embodiment of the present invention includes a sapphire substrate 655 that is a window layer and supporting substrate, and a blue-green InGaN system provided on the sapphire substrate 655. A light-emitting element including a light-emitting portion made of a material and a light-emitting portion made of a red-yellow AlGaInP-based material.

The light emitting portion made of a blue-green InGaN material includes an N-type cladding layer (second semiconductor layer) 651 made of Al _s Ga _1-s N (0 ≦ s ≦ 1), In _s Ga _1-s N (0 ≦ s ≦ 1) and a P-type cladding layer (first semiconductor layer) 653 made of Al _s Ga _1-s N (0 ≦ s ≦ 1) are formed in this order. The P-type cladding layer 653 and the active layer 652 are removed, and a non-removal portion 660 other than the removal portion 670 is provided. Further, the P-type clad layer 653 is provided in the non-removal portion 660. A third electrode (first ohmic electrode) 661 that is in contact with the electrode and a fourth electrode (second ohmic electrode) 671 that is provided in the removal portion 670 and is in contact with the N-type cladding layer 651 are provided.

The light emitting portion made of a red-yellow AlGaInP material is a P-type cladding layer made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6). (First semiconductor layer) 603, active layer 602 made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6), and (Al _x Ga) _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) and an N-type cladding layer (second semiconductor layer) 601 is formed in this order. The N-type cladding layer 601 and the active layer 602 are removed, and a non-removal portion 610 other than the removal portion 620 is provided. The N-type cladding layer 601 is provided in the non-removal portion 610. A first electrode (first ohmic electrode) 611 in contact with the P-type cladding layer 03 and in contact with that second electrode and a (second ohmic electrode) 621. In addition, the light emitting portion made of a red-yellow AlGaInP material is an epitaxial layer (N-type cladding layer 651, active layer 652, and P-type cladding layer 653) constituting the light emitting portion made of a blue-green InGaN material. ) Are joined via two layers of SiO ₂ films 606 and 656.

  Each of the two light emitting portions is covered with an insulating layer 615, and a bump 640 is formed on the first electrode 611, the second electrode 621, the third electrode 661, and the fourth electrode 671. Yes.

Next, the manufacturing method of the light emitting element in the 6th embodiment of this invention is demonstrated with reference to Fig.6 (a)-(h). First, as shown in FIG. 6A, an N-type film made of Al _s Ga _1-s N (0 ≦ s ≦ 1) is formed on a sapphire substrate 655 by, for example, metal organic vapor phase epitaxy (MOVPE). cladding layer (second semiconductor _{layer) 651, In s Ga 1-} s N (0 ≦ s ≦ 1) active layer _{652, Al s Ga 1-s} N (0 ≦ s ≦ 1) P -type cladding layer consisting of consisting of By sequentially laminating (first semiconductor layer) 653, an InGaN-based epitaxial wafer 650 which is a blue / green light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method. Then, an SiO ₂ film 656 is formed on the P-type cladding layer 653.

Further, as shown in FIG. 6B, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x) is formed on the GaAs substrate 605 by, eg, metal organic chemical vapor deposition (MOVPE). ≦ 1, 0.4 ≦ y ≦ 0.6) N-type cladding layer (second semiconductor layer) 601, (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1,0,. Active layer 602 made of 4 ≦ y ≦ 0.6), P-type cladding made of (Al _x Ga _1-x ) _y In _1-y P (0 ≦ x ≦ 1, 0.4 ≦ y ≦ 0.6) By sequentially laminating layers (first semiconductor layers) 603, an AlGaInP-based epitaxial wafer 600 that is a red / yellow light emitting material is manufactured. Note that the manufacturing method is not limited to MOVPE, and may be manufactured by a molecular beam epitaxy (MBE) method or an actinic beam epitaxy (CBE) method. Then, an SiO ₂ film 606 is formed on the P-type cladding layer 603. The SiO ₂ film may be formed on only one of the first epitaxial substrate and the second epitaxial substrate, or may be formed on both.

Next, as shown in FIG. 6C, the InGaN-based epitaxial wafer 650 and the AlGaInP-based epitaxial wafer 600 are bonded. At this time, both the AlGaInP-based epitaxial wafer 600 and the InGaN-based epitaxial wafer 650 are immersed in an alkali solution (KOH aqueous solution or NaOH aqueous solution) to treat the surfaces with alkali, and the SiO _{2 of the} AlGaInP-based epitaxial wafer 600 and the InGaN-based epitaxial wafer 650 is treated. By bringing the films into contact with each other in a vacuum, pressing them together at a pressure of 500 N or higher, and holding them at a temperature of 700 ° C. or higher, it is possible to form a bonded wafer 60 in which both wafers are bonded.

  Next, as shown in FIG. 6D, a wafer 61 is formed by removing the GaAs substrate 605 of the AlGaInP epitaxial wafer 600 by chemical etching. The chemical etchant preferably has an etching selectivity with respect to the AlGaInP-based material, and is generally removed with an ammonia-containing etchant. In this case, the substrate to be processed or removed may be a sapphire substrate 655.

  Next, as shown in FIG. 6 (e), a first electrode (first ohmic electrode) 611 is formed on the N-type cladding layer 601 (non-removed portion 610) of the AlGaInP-based epitaxial wafer 600, and in a region 620. A hole or groove-like shape reaching the P-type cladding layer 603 is formed (that is, the N-type cladding layer 601 and the active layer 602 are removed to provide a removal portion), and the bottom of the region 620 is in contact with the P-type cladding layer 603. Two electrodes (second ohmic electrode) 621 are formed.

Next, as shown in FIG. 6F, a part of the region 630 where the first electrode 611 and the second electrode 621 are not formed is removed from the epitaxial layer made of the AlGaInP-based material. The removal of the region 630 uses an ICP etching method in an atmosphere containing a Cl-based gas (Cl ₂ , BCl ₃ , SiCl ₄ ) to expose the SiO ₂ film 606 formed on the InGaN-based epitaxial wafer. Then, the SiO ₂ films 606 and 656 are removed by an ICP etching method in an atmosphere containing an F-based gas (CF ₄ , CHF ₃ , C ₂ F ₆ , C ₃ F ₈ , NF ₃ , SF ₄ , SF ₆ ). Then, the surface (P-type cladding layer 653) of the InGaN-based epitaxial wafer is exposed.

  Next, as shown in FIG. 6G, a third electrode (first ohmic electrode) 661 is formed on a part (non-removed portion 660) of the P-type cladding layer 653 of the exposed InGaN-based epitaxial wafer 650, A hole or groove-like shape reaching the N-type cladding layer 651 is opened in the region 670 (that is, the removal portion is provided by removing the P-type cladding layer 653 and the active layer 652), and the N-type cladding layer is formed at the bottom of the region 670. A fourth electrode (second ohmic electrode) 671 in contact with 651 is formed.

  Next, as shown in FIG. 6H, bumps 640 are formed on the first electrode 611, the second electrode 621, the third electrode 661, and the fourth electrode 671, and the light emitting wafer (light emitting element) 62 is manufactured. To do. Note that the bumps may be formed of studs or plated.

  In each of the light-emitting elements manufactured in the first to sixth embodiments, the light-emitting portion made of a blue-green InGaN-based material has an N-type cladding from the sapphire substrate (window layer / support substrate) side. A light emitting portion formed of a red-yellow AlGaInP-based material is formed in this order from a layer (second semiconductor layer), an active layer, and a P-type cladding layer (first semiconductor layer) from the sapphire substrate (window layer / support substrate) side. The P-type cladding layer (first semiconductor layer), the active layer, and the N-type cladding layer (second semiconductor layer) are formed in this order, but the present invention is not limited to this. When changing the order of the second semiconductor layer and the first semiconductor layer in each light emitting portion, the second semiconductor layer and the first semiconductor layer are formed when the first epitaxial substrate or the second epitaxial substrate is manufactured. Change the order.

  Further, as shown in the first to sixth embodiments, even when a light emitting portion made of a red-yellow AlGaInP-based material is bonded onto an epitaxial layer made of a blue-green InGaN-based material, The junction surface between the light emitting portion made of a red-yellow AlGaInP material and the epitaxial layer made of a blue-green InGaN material has a high resistance, so that the light emitting portion made of a red-yellow AlGaInP material was energized. At this time, current is not supplied to the epitaxial layer made of a blue-green InGaN material underneath.

(Method for manufacturing light-emitting element array substrate)
Next, an example of a method for manufacturing a light-emitting element array substrate by mounting the light-emitting elements manufactured according to the first to sixth embodiments on a wiring board will be described with reference to FIGS.

  First, as shown in FIG. 7, a blue / green light emitting element FET control unit 701 and a yellow / red light emitting element FET control unit 751 are provided on a Si wafer 700. The FET controllers 701 and 751 each have a source electrode (711, 761), a drain electrode (712, 762), a gate oxide film (713, 763), a gate electrode (714, 764), and an inversion region (715, 765). . The drain electrodes (712, 762) are connected to the source lines (741, 791) via the wirings (740, 790). A pad electrode part (731, 732, 781, 782) is provided on a part of the wiring part (721, 722, 771, 772), and the drive circuit wafer 800 is formed.

  Instead of the driving circuit wafer 800 shown in FIG. 7, a driving circuit wafer 800 'shown in FIG. 8 may be used. As shown in FIG. 8, the drive circuit wafer 800 ′ includes an FET control unit (701 ′, 751 ′), a wiring unit (721 ′, 722 ′, 771 ′, 772 ′) and a pad electrode in the Si wafer 700 ′. It is not formed on the same surface as the portions (731 ′, 732 ′, 781 ′, 782 ′) but on the opposite surface via vias (745 ′, 795 ′). The source electrode (711 ′, 761 ′), the drain electrode (712 ′, 762 ′), the gate oxide film (713 ′, 763 ′), the gate electrode (714 ′, 764 ′), the inversion region (715 ′, 765). '), Wirings (740', 790 '), and source lines (741', 791 ') are formed in the same manner as the drive circuit wafer 800 described above.

  Next, the light emitting wafer (12, 22, 32, 42, 52, 62) and the drive circuit wafer 800 are overlapped and bonded, and the first embodiment will be described as an example. As shown in FIG. 9, the bump 140 on the light emitting wafer 12 and the pad electrode portions (731, 732, 781, 782) on the drive circuit wafer 800 are overlapped with each other, and a pressure of 10 N or more and an ultrasonic wave are applied. The bumps 140 and the pad electrode portions (731, 732, 781, 782) are combined to obtain the light emitting element array substrate 900.

  In the first embodiment, GaN has a refractive index of 2.4 with respect to red to yellow emission wavelengths, and AlGaInP has a refractive index of 3.4. The total reflection angle at this time can obtain a wide light distribution angle of 40 degrees.

In the second and third embodiments, since the bonding is performed via the BCB film and the SiO ₂ film, the refractive index of the SiO ₂ film is 1.5 and the refractive index of AlGaInP is 3.4. The total reflection angle at this time is 24 degrees and the light distribution angle is narrower than that of the first embodiment, but a mechanically stronger joint can be obtained as compared with the first embodiment.

  In the fourth to sixth embodiments, the light emitting layer is not cut out, but a via is formed to make ohmic contact with the lower layer, so that the area of the light emitting layer can be increased, and one element It is possible to realize a light emitting element array in which the hit brightness is increased.

  In the first to third embodiments, the light emitting elements having different emission wavelengths are arranged in the plane direction in order to form one pixel. However, in the fourth to sixth embodiments, in the light extraction direction. A plurality of light emitting elements having a plurality of wavelengths can be provided in a stacked manner, and can be realized only by having an area of one pixel having a minimum area necessary for contact. Therefore, it is possible to design a large element per pixel, and by increasing the element area, characteristic variation per element can be reduced.

  In the first to sixth embodiments, the light emitting part made of a blue-green InGaN-based material and the light emitting part made of a red-yellow AlGaInP-based material are used as the plurality of light emitting parts having different emission wavelengths. Although an example has been shown, the light emitting portion in the present invention is not limited to these, and is of any conventionally known light emission wavelength (material), for example, other than the above materials, ZnSe-based, ZnO-based, GaO-based, etc. The material can be used. And in manufacture of a light emitting element, the epitaxial substrate which has a desired light emission wavelength is prepared as a 1st epitaxial substrate and a 2nd epitaxial substrate, These are joined, The light emission part of several desired light emission wavelength is obtained. A combined light-emitting element can be easily manufactured.

  As described above, in the light-emitting element of the present invention, a plurality of light-emitting portions having different emission wavelengths are formed in one light-emitting element, for example, two or more colors of blue to green and yellow to red A light-emitting element that can display and can emit light to the outside while maintaining high luminance without interfering light of a plurality of wavelengths with each other. Therefore, the light emitting device of the present invention is particularly suitable for a light emitting device array with a narrow pitch. Further, according to the method for manufacturing a light emitting element of the present invention, since light emitting portions having two types of light emission wavelengths are separately formed and then joined, each can be grown under optimum crystal growth conditions. A light-emitting layer (light-emitting element region) that is highly efficient with respect to the wavelength can be obtained. Accordingly, a light-emitting element suitable for a light-emitting element array having a narrow pitch and having a plurality of light-emitting portions having different emission wavelengths and capable of radiating to the outside while maintaining high luminance without causing light of a plurality of wavelengths to interfere with each other Can be easily manufactured.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

10, 20, 30, 40, 50, 60 ... bonded wafer,
11, 21, 31, 41, 51, 61 ... wafers from which the GaAs substrate has been removed,
12, 22, 32, 42, 52, 62 ... light emitting wafer (light emitting element),
100, 200, 300, 400, 500, 600 ... AlGaInP epitaxial wafer,
101, 201, 301, 401, 501, 601 ... N-type cladding layer (second semiconductor layer),
102, 202, 302, 402, 502, 602 ... active layer,
103, 203, 303, 403, 503, 603 ... P-type cladding layer (first semiconductor layer),
105, 205, 305, 405, 505, 605 ... GaAs substrate,
110, 210, 310, 410, 510, 610 ... non-removal part,
111, 211, 311, 411, 511, 611 ... first electrode (first ohmic electrode),
115, 215, 315, 415, 515, 615 ... insulating layer,
120, 220, 320, 420, 520, 620 ... removal unit,
121, 221, 321, 421, 521, 621, second electrode (second ohmic electrode),
130, 230, 330, 430, 530, 630 ... a region where the first electrode and the second electrode are not formed,
140, 240, 340, 440, 540, 640 ... bumps,
150, 250, 350, 450, 550, 650 ... InGaN epitaxial wafer,
151, 251, 351, 451, 551, 651... N-type cladding layer (second semiconductor layer),
152, 252, 352, 452, 552, 652 ... active layer,
153, 253, 353, 453, 553, 653... P-type cladding layer (first semiconductor layer),
155, 255, 355, 455, 555, 655 ... sapphire substrate (window layer and supporting substrate),
160, 260, 360, 460, 560, 660 ... non-removal part,
161, 261, 361, 461, 561, 661 ... third electrode (first ohmic electrode),
170, 270, 370, 470, 570, 670 ... removal section,
171, 271, 371, 471, 571, 671 ... fourth electrode (second ohmic electrode),
204, 504 ... benzocyclobutene (BCB) film,
306, 356, 606, 656... SiO ₂ film,
700, 700 '... Si wafer,
701, 701 '... FET control unit for blue / green light emitting element,
711, 761, 711 ', 761' ... source electrode,
712, 762, 712 ′, 762 ′... Drain electrode,
713, 763, 713 ′, 763 ′... Gate oxide film,
714, 764, 714 ′, 764 ′... Gate electrode,
715, 765, 715 ', 765' ... inversion region,
721, 722, 771, 772, 721 ′, 722 ′, 771 ′, 772 ′... Wiring section,
731, 732, 781, 782, 731 ′, 732 ′, 781 ′, 782 ′ ... pad electrode part,
740, 790, 740 ', 790' ... wiring,
741, 791, 741 ', 791' ... source line,
745 ', 795' ... via,
751, 751 '... FET control unit for yellow / red light emitting element,
800, 800 '... drive circuit wafer,
900: Light emitting element array substrate.

Claims (10)

A light-emitting element comprising a window layer / support substrate and a plurality of light emitting portions having different emission wavelengths provided on the window layer / support substrate,
Each of the plurality of light emitting units has a structure in which a second conductive type second semiconductor layer, an active layer, and a first conductive type first semiconductor layer are formed in this order, and the first semiconductor layer Or a removed portion from which the second semiconductor layer and the active layer are removed, a non-removed portion other than the removed portion, and a first ohmic electrode provided in the non-removed portion, and the removed And a second ohmic electrode provided on the portion.   One of the plurality of light emitting units is composed of an epitaxial layer formed directly on the window layer / supporting substrate, and the other light emitting unit is joined on the epitaxial layer. The light emitting element according to claim 1, wherein the light emitting element is provided. The benzocyclobutene film or the SiO ₂ film is provided between the epitaxial layer directly formed on the window layer / support substrate and the light emitting portion bonded on the epitaxial layer. 2. The light emitting device according to 2.   The plurality of light emitting portions include a light emitting portion made of a blue-green InGaN-based material and a light emitting portion made of a red-yellow AlGaInP-based material. The light emitting element according to item. A method of manufacturing a light emitting device,
A first epitaxial substrate on which an epitaxial layer that emits light of the first wavelength is grown on the first substrate, and an epitaxial layer that emits light of the second wavelength on the second substrate are grown. Preparing a second epitaxial substrate;
Bonding the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate;
Removing the first substrate or the second substrate from the bonded epitaxial substrate;
A method for manufacturing a light-emitting element, comprising:   6. The light emitting device according to claim 5, wherein the epitaxial layer that emits light of the first wavelength is an InGaN-based material, and the epitaxial layer that emits light of the second wavelength is an AlGaInP-based material. Device manufacturing method.   As an epitaxial layer for emitting light of the first wavelength and an epitaxial layer for emitting light of the second wavelength, a second conductive type second semiconductor layer, an active layer, and a first conductive type first semiconductor layer The method for manufacturing a light emitting element according to claim 5, wherein an epitaxial layer having a structure in which and are formed in this order is formed.   After the step of removing the first substrate or the second substrate, in each of the epitaxial layer that emits light of the first wavelength and the epitaxial layer that emits light of the second wavelength, the first A removed portion from which the semiconductor layer or the second semiconductor layer and the active layer are removed and a non-removed portion other than the removed portion are formed, a first ohmic electrode is provided in the non-removed portion, and a second is provided in the removed portion. The method for manufacturing a light emitting element according to claim 7, further comprising a step of providing an ohmic electrode.   Before the step of bonding the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate, at least one of the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate A benzocyclobutene film is formed on the first epitaxial substrate, and then the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate are bonded together via the benzocyclobutene film. The manufacturing method of the light emitting element as described in any one of Claims 5-8. Before the step of bonding the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate, at least one of the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate 6. An SiO ₂ film is formed on the first epitaxial substrate, and then the epitaxial layer of the first epitaxial substrate and the epitaxial layer of the second epitaxial substrate are bonded together via the SiO ₂ film. The manufacturing method of the light emitting element as described in any one of Claim 8.

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