JP4927223B2 - LIGHT EMITTING ELEMENT AND ITS MANUFACTURING METHOD, LIGHT EMITTING DEVICE MANUFACTURING METHOD, LIGHTING DEVICE, BACKLIGHT AND DISPLAY DEVICE - Google Patents

Description

  The present invention relates to a light emitting element having a protruding semiconductor such as a rod or plate, a method for manufacturing the same, a method for manufacturing a light emitting device including the light emitting element, and an illumination device, a backlight, and a display device including the light emitting device. About.

  Conventionally, a rod-type light-emitting element having a light-emitting area increased as compared with a planar light-emitting element is disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2006-332650).

  As shown in FIG. 24, the rod-type light emitting device has a first polar layer 910 formed on a substrate 900, and a plurality of rods 920 made of an active layer that emits light is formed on the first polar layer 910. Has been. The rod 920 is further encapsulated in a second polar layer 930, and the plurality of rods 920 and the second polar layer 930 made of the active layer constitute a rod-type light emitting element.

  According to the above prior art, each rod 920 emits light to the entire surface, so that the light emitting area is increased and the amount of light by the light emitting element is increased.

  However, in the above prior art, the rod 920 is composed of an active layer, and the active layer has a role of exclusively confining carriers to increase the light emission efficiency, and generally has a high resistance. In the above prior art, in order to increase the light emitting area, it is necessary to increase the length of the rod. However, as the length of the rod is increased, the active layer having a high resistance becomes longer, and a sufficient current can flow to the tip. There was a problem that the tip end portion became dark without being able to be obtained and sufficient light emission intensity could not be obtained.

JP 2006-332650 A

  Accordingly, an object of the present invention is to provide a light emitting element that can obtain a sufficient light emission intensity with low resistance. The present invention further provides a method for manufacturing such a light-emitting element, a method for manufacturing a light-emitting device using such a light-emitting element, a lighting device including such a light-emitting device, a backlight, and a display device. There is.

In order to solve the above problems, a light emitting device of the present invention includes a first conductivity type semiconductor base,
A plurality of first-conductivity-type protruding compound semiconductors formed to project and extend on the first-conductivity-type semiconductor base;
A second conductive type compound semiconductor layer serving as a shell covering at least the side surface of the protruding compound semiconductor;
While light is emitted between the side surface of the first conductive type protruding compound semiconductor and the second conductive type compound semiconductor layer,
E Bei transparent electrode layer <br/> covering the side surface of the shell to become the second conductive type compound semiconductor layer which covers the protruding compound semiconductor side surface of the first conductivity type,
The first conductive type protruding compound semiconductor is a first conductive type plate compound semiconductor;
The plate compound semiconductor of the first conductivity type has a rectangular cross section, and the side surface on the long side of the plate compound semiconductor having a rectangular cross section is a light emitting surface having a nonpolar surface .

  According to the light emitting device of the present invention, since the second conductive type semiconductor layer is formed so as to cover the first conductive type protruding semiconductor, almost all side surfaces of the protruding semiconductor can be made to emit light. It becomes. Therefore, according to the light emitting device of the present invention, the light emission amount per unit area of the first conductivity type semiconductor base can be increased as compared with a light emitting diode chip having a planar light emitting layer.

  Further, according to the present invention, since the protruding semiconductor is made of the first conductivity type semiconductor, the resistance can be easily reduced by increasing the amount of impurities imparting the first conductivity type to the protruding semiconductor. Therefore, even if the length of the protruding semiconductor is increased, an increase in the resistance of the protruding semiconductor is suppressed, and light can be emitted uniformly from the root portion to the tip portion of the protruding semiconductor. Therefore, it is possible to further increase the light emission amount per unit area of the first conductivity type semiconductor base.

  In one embodiment, the first conductivity type protruding semiconductor is a first conductivity type rod-shaped semiconductor.

  According to this embodiment, since light can be emitted uniformly from the root portion to the tip portion of the rod-shaped semiconductor, and almost all side surfaces of the rod-shaped semiconductor can be light-emitted, a planar light emitting layer is provided. Compared with the light emitting diode chip, the light emission amount per unit area of the semiconductor base of the first conductivity type can be increased.

  In one embodiment, the length of the first conductivity type rod-shaped semiconductor is 10 times or more the thickness of the first conductivity type rod-shaped semiconductor.

  In this embodiment, the amount of light emission per unit area of the semiconductor base can be remarkably increased. On the other hand, when the rod-shaped semiconductor is made of an active layer as in the prior art, it is difficult to emit light at the tip if the length of the rod-shaped semiconductor is 10 times or more the thickness. Therefore, when the length of the rod-shaped semiconductor is 10 times or more of the thickness, the advantage of the present invention that the light emission intensity is high with low resistance becomes particularly remarkable.

  In one embodiment, the first conductive type protruding semiconductor is a first conductive type semiconductor plate.

  According to this embodiment, since the projecting semiconductor is a plate semiconductor, the widest light emission surface of the plate semiconductor is a nonpolar surface, so that the overall light emission efficiency can be increased.

  In one embodiment, an active layer is formed between the first conductive type protruding semiconductor and the second conductive type semiconductor layer.

  In this embodiment, the luminous efficiency can be increased. Further, since the active layer is formed to be relatively thin between the first conductive type protruding semiconductor and the second conductive type semiconductor layer, the luminous efficiency is high. This is because the active layer is for confining bipolar carriers (holes and electrons) in a narrow range to increase the recombination probability. On the other hand, when all of the first conductive type rod-shaped semiconductor portion is made of an active layer as in the prior art, the light emission efficiency is not high because of insufficient carrier confinement.

  In one embodiment, a transparent electrode layer is formed on the second conductivity type semiconductor layer.

  In this embodiment, it is possible to prevent a voltage drop in the second conductivity type semiconductor layer while the transparent electrode layer transmits light emitted from the rod-shaped semiconductor. Therefore, light can be emitted uniformly over the entire rod-shaped semiconductor.

  In one embodiment, a transparent member made of a material having higher transparency than the transparent electrode layer in a facing gap where the transparent electrode layer is opposed between the plurality of first conductive type protruding semiconductors. Is filled.

  In this embodiment, a transparent member having higher transparency than the transparent electrode layer without filling the gaps between the plurality of first conductive type protruding semiconductors with a transparent electrode layer having generally low transparency. Is filled in the facing gap, so that the light emission efficiency of the light emitting element can be improved.

Further, the method for manufacturing a light-emitting element according to the present invention includes a step of patterning a mask layer on the surface of a first conductivity type semiconductor layer forming part or all of the first substrate;
Forming a plurality of first-conductivity-type protruding semiconductors by anisotropically etching the semiconductor layer using the mask layer as a mask;
A semiconductor shell forming step of forming a second conductivity type semiconductor layer so as to cover the surface of the first conductivity type protruding semiconductor.

  According to the manufacturing method of the present invention, in the manufactured light emitting element, since the second conductive type semiconductor layer is formed so as to cover the first conductive type protruding semiconductor, almost all side surfaces of the protruding semiconductor are formed. Can be emitted. Therefore, according to the light emitting element, it is possible to increase the light emission amount per unit area of the first substrate as compared with a light emitting diode chip having a planar light emitting layer. Further, according to this manufacturing method, since the protruding semiconductor is made of a first conductivity type semiconductor, the resistance can be easily reduced by increasing the amount of impurities that give the first conductivity type to the protruding semiconductor. Therefore, even if the length of the protruding semiconductor is increased, an increase in the resistance of the protruding semiconductor is suppressed, and light can be emitted uniformly from the root portion to the tip portion of the protruding semiconductor. Therefore, it is possible to further increase the light emission amount per unit area of the first substrate. Furthermore, according to this manufacturing method, since the protruding semiconductor can be formed by anisotropic etching with the photolithography process, a protruding semiconductor having a favorable shape can be obtained and the yield can be improved. Can do.

  The method of manufacturing a light emitting device according to an embodiment includes a crystal defect recovery step of annealing the first conductive type protruding semiconductor after the semiconductor core formation step and before the semiconductor shell formation step. Do.

  According to this embodiment, the crystal defect density of the protruding semiconductor can be reduced and the crystallinity can be improved by the crystal defect recovery step by the annealing. Accordingly, in the subsequent semiconductor shell formation step, the crystallinity of the second conductivity type semiconductor layer is also improved, so that the light emission efficiency of the light emitting element can be improved.

  Also, in one embodiment of the method for manufacturing a light emitting device, after the semiconductor core formation step and before the shell formation step, a part of the first conductive type protruding semiconductor is etched by wet etching. A crystal defect removal step is performed.

  According to this embodiment, the crystal defect density of the protruding semiconductor can be reduced and the crystallinity can be improved by the crystal defect removal step by the etching. Accordingly, in the subsequent semiconductor shell formation step, the crystallinity of the second conductivity type semiconductor layer is also improved, so that the light emission efficiency of the light emitting element can be improved.

Also, in one embodiment of the method for manufacturing a light emitting device, after the semiconductor core formation step and before the shell formation step, a part of the first conductive type protruding semiconductor is etched by wet etching. A crystal defect removal step;
After the semiconductor core formation step and before the semiconductor shell formation step, the crystal defect recovery step of annealing the first conductive type protruding semiconductor is the crystal defect removal step, the crystal defect recovery step In order.

  According to this embodiment, by performing both the crystal defect removal step by wet etching and the crystal defect recovery step by annealing in this order, the crystallinity of the protruding semiconductor can be more effectively improved. Can do.

Further, the method for manufacturing a light-emitting element according to the present invention includes a step of patterning a mask layer on the surface of a first conductivity type semiconductor layer forming part or all of the first substrate;
Forming a plurality of first-conductivity-type protruding semiconductors by anisotropically etching the semiconductor layer using the mask layer as a mask;
A semiconductor shell forming step of forming a second conductive type semiconductor layer so as to cover the surface of the first conductive type protruding semiconductor;
A light emitting element separating step of separating the first conductive type protruding semiconductor covered with the second conductive type semiconductor layer from the first substrate.

  According to the manufacturing method of the present invention, the protruding light emitting elements formed by the protruding semiconductor formed by processing the semiconductor layer of the first conductivity type in the step of separating the light emitting elements are finally independent of each other. It becomes the light emitting element which became. Therefore, the use method of the projection-like light emitting elements can be diversified and the utility value can be increased in that each light emitting element can be used individually. For example, a desired number of separated light emitting elements can be arranged at a desired density. In this case, for example, a surface light-emitting device can be configured by rearranging a large number of fine light-emitting elements on a large-area substrate. In addition, the heat generation density can be lowered to achieve high reliability and long life. In addition, since the second conductive type semiconductor layer is formed so as to cover the first conductive type protruding semiconductor by this manufacturing method, light can be emitted from almost all side surfaces of the protruding semiconductor. . Therefore, a large number of light emitting elements having a large total light emission amount can be obtained from the substrate (first substrate). Further, according to this manufacturing method, since the protruding semiconductor is made of a first conductivity type semiconductor, the resistance can be easily reduced by increasing the amount of impurities that give the first conductivity type to the protruding semiconductor. Therefore, even if the length of the protruding semiconductor is increased, an increase in the resistance of the protruding semiconductor is suppressed, and light can be emitted uniformly from the root portion to the tip portion of the protruding semiconductor. Furthermore, according to this manufacturing method, since the protruding semiconductor can be formed by anisotropic etching with a photolithography process, a protruding semiconductor having a good shape as intended can be obtained, and consequently desired good Since a light-emitting element having a shape can be obtained, the yield of the light-emitting elements can be improved.

  In one embodiment, an active layer is formed between the semiconductor core forming step and the semiconductor shell forming step so as to cover the surface of the first conductive type protruding semiconductor.

  According to this embodiment, the luminous efficiency can be increased in the active layer.

  In one embodiment, the transparent electrode layer is formed so as to cover the second conductivity type semiconductor layer after the semiconductor shell formation step.

  According to this embodiment, the transparent electrode layer can prevent a voltage drop from occurring in the second conductive type semiconductor layer while transmitting the light emitted from the protruding semiconductor. Therefore, light can be emitted uniformly over the entire protruding semiconductor.

Further, in the method for manufacturing a light emitting device of the present invention, a step of patterning a mask layer on the surface of the first conductivity type semiconductor layer forming part or all of the first substrate;
Forming a plurality of first-conductivity-type protruding semiconductors by anisotropically etching the semiconductor layer using the mask layer as a mask;
A semiconductor shell forming step of forming a second conductive type semiconductor layer so as to cover the surface of the first conductive type protruding semiconductor;
A light emitting element separating step of separating the first conductive type protruding semiconductor covered with the second conductive type semiconductor layer from the first substrate to obtain a light emitting element;
A light emitting element disposing step of disposing the light emitting element on the second substrate;
And a light emitting element wiring step of performing wiring for energizing the light emitting elements disposed on the second substrate.

  According to the manufacturing method of the present invention, a desired number of light emitting elements separated in the light emitting element separating step can be arranged on the second substrate with a desired density. Therefore, for example, a surface light-emitting device can be configured by rearranging a large number of fine light-emitting elements on a large-area substrate. In addition, the heat generation density can be lowered to achieve high reliability and long life.

  Moreover, the illuminating device of one Embodiment was equipped with the light-emitting device manufactured by the manufacturing method of the said light-emitting device.

  According to the lighting device of this embodiment, since the light emitting device manufactured by the method for manufacturing a light emitting device of the present invention is provided, a lighting device with high luminous efficiency and high reliability can be obtained.

  In addition, a liquid crystal backlight according to an embodiment includes a light emitting device manufactured by the method for manufacturing a light emitting device.

  According to the liquid crystal backlight of this embodiment, since the light emitting device manufactured by the method for manufacturing a light emitting device of the present invention is provided, a backlight with high heat dissipation efficiency can be obtained.

According to another aspect of the present invention, there is provided a method for manufacturing a display device, comprising: patterning a mask layer on a surface of a first conductivity type semiconductor layer that forms part or all of a first substrate;
Forming a plurality of first-conductivity-type protruding semiconductors by anisotropically etching the semiconductor layer using the mask layer as a mask;
A semiconductor shell forming step of forming a second conductive type semiconductor layer so as to cover the surface of the first conductive type protruding semiconductor;
A light emitting element separating step of separating the first conductive type protruding semiconductor covered with the second conductive type semiconductor layer from the first substrate to obtain a light emitting element;
A light emitting element arranging step of arranging the light emitting element corresponding to a pixel position on the second substrate;
And a light emitting element wiring step for performing wiring for energizing the light emitting elements arranged corresponding to the pixel positions on the second substrate.

  According to the method for manufacturing a display device of the present invention, since the second conductive type semiconductor layer is formed so as to cover the surface of the first conductive type protruding semiconductor, the first conductive material as the protruding semiconductor material is formed. The light emission area per unit area of the substrate can be greatly increased. That is, it is possible to greatly reduce the manufacturing cost of the first conductive type protruding semiconductor covered with the second conductive type semiconductor layer functioning as a light emitting element. The protruding semiconductor of the first conductivity type covered with the semiconductor layer of the second conductivity type is separated from the first substrate and disposed on the second substrate serving as a panel of the display device. The display device is manufactured by wiring. Since the number of pixels of this display device is about 6 million, for example, when a light emitting element is used for each pixel, the cost of the light emitting element is extremely important. Therefore, the manufacturing cost of the display device can be reduced by manufacturing the display device by this manufacturing method.

  Moreover, the display apparatus of one Embodiment was manufactured by the manufacturing method of the said display apparatus.

  According to the display device of this embodiment, a low-cost display device is provided.

  According to the light emitting device of the present invention, since the protruding semiconductor is made of the first conductivity type semiconductor, the resistance of the protruding semiconductor can be easily reduced by increasing the amount of impurities that give the first conductivity type to the protruding semiconductor. it can. Therefore, even if the length of the protruding semiconductor is increased, an increase in the resistance of the protruding semiconductor is suppressed, and light can be emitted uniformly from the root portion to the tip portion of the protruding semiconductor. Therefore, it is possible to further increase the light emission amount per unit area of the first conductivity type semiconductor base.

It is sectional drawing of 1st Embodiment of the light emitting element of this invention. It is a schematic plan view of the first embodiment. It is a figure explaining the manufacturing method of the light emitting element of the said 1st Embodiment. It is a figure explaining the manufacturing method of the light emitting element of the said 1st Embodiment. It is a top view explaining the manufacturing method of the light emitting element of the said 1st Embodiment. It is a figure explaining the manufacturing method of the light emitting element of the said 1st Embodiment. It is a figure explaining the manufacturing method of the light emitting element of the said 1st Embodiment. It is a figure explaining the manufacturing method of the light emitting element of the said 1st Embodiment. It is sectional drawing of 2nd Embodiment of the light emitting element of this invention. It is the schematic plan view which looked at the light emitting element of the said 2nd Embodiment from the top. It is a schematic plan view explaining the manufacturing method of the light emitting element of the said 2nd Embodiment. It is a figure explaining the manufacturing method of the light emitting element of 3rd Embodiment of this invention, and a light-emitting device. It is a figure explaining the manufacturing method of the said 3rd Embodiment. It is a figure explaining the manufacturing method of the said 3rd Embodiment. It is a figure explaining the manufacturing method of the said 3rd Embodiment. It is a wave form diagram which shows the voltage waveform applied between electrodes in the manufacturing method of the said 3rd Embodiment. It is a figure explaining the manufacturing method of the said 3rd Embodiment. It is a figure explaining the manufacturing method of the said 3rd Embodiment. It is a figure explaining the manufacturing method of the said 3rd Embodiment. It is a figure explaining the manufacturing method of the said 3rd Embodiment. It is a figure explaining the manufacturing method of the said 3rd Embodiment. It is a side view of the illuminating device as 4th Embodiment of this invention. It is a side view of the light emission part of the said illuminating device. It is a top view of the light emission part of the said illuminating device. It is a top view of the light-emitting device of the said light emission part. It is a top view which shows the backlight as 5th Embodiment of this invention. It is a circuit diagram which shows the circuit of 1 pixel of the LED display as 6th Embodiment of this invention. It is a figure which shows the conventional light emitting element.

  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

(First embodiment)
A first embodiment of the light emitting device of the present invention will be described with reference to FIGS. 1A and 1B and FIGS. FIG. 1A is a cross-sectional view of the light emitting device of the first embodiment, and FIG. 1B is a view of the light emitting device of the first embodiment as viewed from above, and is a diagram exclusively showing the position of the rod-shaped semiconductor, 2-6 is a figure explaining the manufacturing method of the light emitting element of this 1st Embodiment. The light emitting device 100 according to the first embodiment includes an n-type semiconductor layer 113 as a first conductivity type semiconductor base, a plurality of n-type rod-shaped semiconductors 121 formed on the n-type semiconductor layer 113, and And a p-type semiconductor layer 123 as a second conductivity type semiconductor layer covering the rod-shaped (projection-shaped) semiconductor 121. As the first conductivity type semiconductor base, a p-type semiconductor layer may be provided instead of the n-type semiconductor layer 113. In this case, an n-type semiconductor layer is provided instead of the p-type semiconductor layer 123 as the second conductivity type semiconductor layer. That is, when the semiconductor layer 113 forming the first conductivity type semiconductor base is p-type, the semiconductor layer 123 forming the second conductivity type semiconductor layer is n-type and the semiconductor layer 113 is n-type. The semiconductor layer 123 is p-type. Hereinafter, as an example, a case where the semiconductor layer 113 as the first conductivity type semiconductor base and the first conductivity type rod-shaped semiconductor 121 are n-type and the second conductivity type semiconductor layer 123 is p-type will be described. However, in the following description, the n-type and the p-type are interchanged so that the semiconductor layer 113 as the first conductive type semiconductor base and the first conductive type rod-shaped semiconductor 121 are set as the p-type and the second conductive type. This can be an explanation of an example in which the n-type semiconductor layer 123 is used.

  In the light emitting device 100 of the first embodiment, as shown in FIGS. 1A and 1B, an n-type semiconductor layer 113 serving as a first conductivity type semiconductor base is formed on a substrate 111, and this n-type semiconductor is formed. A plurality of n-type rod-shaped semiconductors 121 as first-conductivity-type rod-shaped semiconductors are formed on the layer 113 at intervals from each other. The entire surfaces of the n-type rod-shaped semiconductor 121 and the n-type semiconductor layer 113 are covered with an active layer 122. A p-type semiconductor layer 123 is formed on the entire surface of the active layer 122. Further, the entire surface of the p-type semiconductor layer 123 is covered with a transparent electrode layer 124. A transparent electrode layer 124 covering the active layer 122 covering the rod-shaped semiconductor 121 is opposed to the gap between the plurality of n-type rod-shaped semiconductors 121 with a gap therebetween. The gap facing the transparent electrode layer 124 is filled with a transparent member 131 having a higher transparency than the transparent electrode layer 124.

  In the transparent member 131, the transparent electrode layer 124 is not covered with the transparent member 131, but is covered with the upper electrode 141 above the rod-shaped semiconductor 121. That is, as shown in FIG. 1A, the upper electrode 141 is formed on the transparent member 131 that fills the gap where the transparent electrode layer 124 faces and the transparent electrode layer 124 that covers the upper portion of the rod-shaped semiconductor 121. Yes. Thereby, the transparent electrode layer 124 is electrically connected to the upper electrode 141.

  The substrate 111 may be made of an insulator such as sapphire, a semiconductor such as silicon, but is not limited thereto. The n-type semiconductor layer 113, the n-type rod-shaped semiconductor 121, and the p-type semiconductor layer 123 are formed using a semiconductor whose base material is GaN, GaAs, AlGaAs, GaAsP, InGaN, AlGaN, GaP, ZnSe, AlGaInP, or the like. Also good. As the active layer 122, for example, when GaN is selected as the n-type semiconductor layer 113, the n-type rod-shaped semiconductor 121, and the p-type semiconductor layer 123, InGaN can be used. Further, as the transparent electrode layer 124, for example, ITO, ZnO, SnO or the like can be used. The transparent member 131 can be made of, for example, a silicon oxide film or a transparent resin. As the upper electrode 141, a metal such as gold, silver, copper, aluminum, or tungsten, or a transparent electrode such as ITO, ZnO, or SnO can be used. However, when a substrate such as a silicon substrate that does not transmit light is used as the substrate 111, it is necessary to select a transparent electrode that transmits light as the upper electrode 141.

  The thickness of each portion is, for example, that the thickness of the n-type semiconductor layer 113 as the semiconductor base is 5 μm, the thickness D of the n-type semiconductor rod 121 is 1 μm, the length L is 20 μm, and the n-type semiconductor rod The spacing P between 121 may be 3 μm, the thickness of the active layer 122 may be 10 nm, the thickness of the p-type semiconductor layer 123 may be 150 nm, and the thickness of the transparent electrode layer 124 may be 150 nm.

  In this embodiment, unless otherwise specified, the substrate 111 is a silicon substrate, the n-type semiconductor layer 113, the n-type rod-shaped semiconductor 121 and the p-type semiconductor layer 123 is GaN, the active layer 122 is InGaN, and is transparent. ITO is used as the electrode layer 124, a silicon oxide film is used as the transparent member 131, and ITO is used as the upper electrode 141. Moreover, said example is used for the film thickness of each part. In the above description, the first conductivity type is n-type and the second conductivity type is p-type. However, as described above, the first conductivity type may be p-type and the second conductivity type may be n-type.

  In the light emitting device of this embodiment, the n-type semiconductor layer 113 forms a lower electrode (cathode), and a current is passed between the lower electrode (cathode) and the upper electrode (anode) 141, whereby the light emitting device (light emission). Diode).

  In the light emitting element of this embodiment, since the p-type semiconductor layer 123 is formed so as to cover the n-type rod-shaped semiconductor 121, almost all side surfaces of the rod-shaped semiconductor 121 emit light. Therefore, the light emission amount per area of the substrate 111 can be increased as compared with a light emitting diode chip having a planar light emitting layer.

  Further, the light emission amount per unit area of the substrate 111 can be increased as the length L of the rod-shaped semiconductor 121 is increased. In the light emitting device of this embodiment, the rod-shaped semiconductor 121 is made of an n-type semiconductor, and the resistance of the rod-shaped semiconductor 121 can be easily reduced by increasing the amount of impurities that give the rod-shaped semiconductor 121 n-type. Therefore, even if the length L of the rod-shaped semiconductor 121 is increased, light can be emitted uniformly from the root portion to the tip portion of the rod-shaped semiconductor 121. Therefore, it is possible to further increase the light emission amount per area of the substrate 111.

  Regarding the length L and thickness D of the n-type semiconductor rod 121, the value (L / D) obtained by dividing the length L by the thickness D is 10 or more, that is, the length L is 10 times or more the thickness D. It is preferable that This is because the light emission amount per unit area of the substrate 111 can be remarkably increased. On the other hand, when the rod-shaped semiconductor is made of an active layer as in the prior art, if the value (L / D) obtained by dividing the length L of the rod-shaped semiconductor by the thickness D is 10 or more, the tip of the rod-shaped semiconductor It becomes difficult to cause the part to emit light. Therefore, when the value (L / D) obtained by dividing the length L by the thickness D is 10 or more, the advantage of the low resistance and high emission intensity of the present invention is particularly remarkable. The value (L / D) is difficult to be 50 or more with the current technology, and the resistance of the first conductivity type rod-shaped semiconductor 121 cannot be ignored. In addition, the light emitting area (the total area of the active layer 122 in this embodiment) is preferably set to be three times or more the area of the n-type semiconductor layer 113 as the semiconductor base. Here, the area of the n-type semiconductor layer 113 refers to the n-type rod-shaped semiconductor 121 and structures on the n-type rod-shaped semiconductor 121 (the active layer 122, the p-type semiconductor layer 123, the transparent electrode layer 124, the transparent member 131). Etc.) is taken as the area of the flat semiconductor layer 113. In such a case, the amount of light emission per unit area of the substrate 111 is large, and a cost reduction effect can be sufficiently obtained.

  In this embodiment, the active layer 122 is formed between the n-type rod-shaped semiconductor 121 and the p-type semiconductor layer 123, but this is not essential. However, it is preferable to provide the active layer 122, which can increase luminous efficiency. Further, since the active layer 122 is formed between the n-type rod-shaped semiconductor 121 and the p-type semiconductor layer 123 to a thickness of, for example, 10 nm, the luminous efficiency is good. This is because the active layer is provided to increase the recombination probability by confining bipolar carriers (holes and electrons) in a narrow range. As in the prior art, when all of the rod-shaped semiconductor portion is made of an active layer, the light emission efficiency is not high due to insufficient carrier confinement.

  Further, although the transparent electrode layer 124 is formed on the p-type semiconductor layer 123, this is not essential. However, it is preferable to provide the transparent electrode layer 124, and the presence of the transparent electrode layer 124 causes the voltage drop in the p-type semiconductor layer 123 while the transparent electrode layer 124 transmits light emitted from the active layer 122. Can be prevented. Therefore, light can be emitted uniformly over the entire rod-shaped semiconductor 121.

  Furthermore, even when the transparent electrode layer 124 is formed on the p-type semiconductor layer 123, all the gaps between the plurality of n-type rod-shaped semiconductors 121 may not be filled with the transparent electrode layer 124. preferable. That is, after forming the thin transparent electrode layer 124 on the p-type semiconductor layer 123, the opposing gap in which the transparent electrode layer 124 is opposed to the gap between the plurality of n-type rod-shaped semiconductors 121 is formed as described above. It is preferable to fill with a transparent member 131 made of a material having higher transparency than the transparent electrode layer 124. This is because the transparent electrode layer 124 generally has carriers for flowing current, and thus the transparency is poor. Therefore, by filling the gaps between the plurality of n-type rod-shaped semiconductors 121 with the transparent member 131 made of a silicon oxide film or a transparent resin, the light emission efficiency of the light emitting element can be improved.

  In the light emitting device 100 of this embodiment, the active layer 122, the p-type semiconductor layer 123, and the transparent electrode layer 124 cover the entire surfaces of the n-type rod-shaped semiconductor 121 and the n-type semiconductor layer 113. It is not always necessary to cover the entire surface. That is, the active layer 122, the p-type semiconductor layer 123, and the transparent electrode layer 124 only need to cover at least the n-type rod-shaped semiconductor 121. This is because the active layer 122, the p-type semiconductor layer 123, and the transparent electrode layer 124 cover the n-type rod-shaped semiconductor 121, thereby increasing the light emission amount per area of the substrate 111.

  Next, a method for manufacturing the light emitting device 100 according to the first embodiment will be described with reference to FIGS. 2, 3A, 3B, and 4 to 6. FIG.

  First, as shown in FIG. 2, a semiconductor layer 112 made of n-type GaN is formed as a first conductivity type semiconductor layer on a substrate 111 made of silicon to a thickness of 25 μm by MOCVD. At this point, the substrate 111 made of silicon and the semiconductor layer 112 made of n-type GaN are integrated to form the first substrate 110. In other words, the semiconductor layer 112 made of n-type GaN forms part of the first substrate 110. Further, instead of performing such a procedure, a single layer substrate made of n-type GaN may be prepared. In this case, the first conductivity type semiconductor layer made of n-type GaN is the first substrate. It can be said that it does everything.

  Next, as shown in FIGS. 3A and 3B (viewed from above in FIG. 3A), a photoresist is formed on the semiconductor layer 112 made of n-type GaN as the first conductivity type semiconductor layer by a photolithography process. 151 is patterned. At this time, for example, a silicon oxide film may be formed on the entire surface of the semiconductor layer 112 made of n-type GaN as the first conductivity type semiconductor layer, and the silicon oxide film may be patterned by a photolithography process and an etching process. Good.

  Next, as shown in FIG. 4, by using the patterned photoresist 151 as a mask, the semiconductor layer 112 made of n-type GaN as the first conductivity type semiconductor layer is anisotropically dry-etched to perform n-type etching. A rod-like (projection-like) semiconductor 121 made of GaN is formed (semiconductor core forming step). At this time, etching is performed so that the semiconductor layer 112 made of n-type GaN remains with a thickness of about 5 μm, and the remaining portion becomes the semiconductor layer 113 made of n-type GaN. The length L of the first conductivity type rod-shaped semiconductor 121 made of n-type GaN is 20 μm. A plurality of the rod-shaped semiconductors 121 are formed on the n-type GaN semiconductor layer 113 in a standing state with a space therebetween.

  Here, in order to recover or remove crystal defects generated in the rod-shaped semiconductor 121 by the dry etching, it is preferable to perform the following steps.

(Annealing process)
In order to recover crystal defects generated in the rod-shaped semiconductor 121 after the semiconductor core formation step and before the semiconductor shell formation step described later, the substrate 111 on which the rod-shaped semiconductor 121 is formed is annealed in a nitrogen atmosphere. (Crystal defect recovery step). Thereby, the rod-shaped semiconductor 121 is annealed. This annealing temperature can be performed at 600 ° C. to 1200 ° C., for example, when the rod-shaped semiconductor 121 is made of n-type GaN. A more preferable annealing temperature when the rod-shaped semiconductor 121 is made of n-type GaN is 700 ° C. to 900 ° C. at which crystal defect recovery of GaN is remarkable and GaN does not decompose.

(Wet etching process)
After the semiconductor core formation step and before the semiconductor shell formation step, which will be described later, the substrate 111 on which the rod-shaped semiconductor 121 is formed is wet-etched, and a layer containing crystal defects generated in the rod-shaped semiconductor 121 at a high density Are selectively removed (crystal defect removal step). For example, when the rod-shaped semiconductor 121 is n-type GaN, hot phosphoric acid heated to 120 ° C. to 150 ° C. may be used as the etching solution.

  By performing the crystal defect recovery step (annealing step) or the crystal defect removal step (wet etching step), the crystal defect density of the rod-shaped semiconductor 121 can be reduced and the crystallinity can be improved. Accordingly, in the subsequent semiconductor shell formation step, the crystallinity of the active layer (light emitting layer) 122 and the second conductivity type semiconductor layer 123 is also improved, so that the light emission efficiency of the light emitting element can be improved.

  The crystal defect removal step (wet etching step) and the crystal defect recovery step (annealing step) are both performed in the order of the wet etching step and the annealing step (that is, after performing the wet etching step, By performing the annealing step), the crystallinity of the rod-shaped semiconductor 121 can be more effectively improved.

  Next, as shown in FIG. 5, the entire surface of the semiconductor layer 113 made of n-type GaN as the first conductivity type semiconductor base and the rod-shaped semiconductor 121 made of n-type GaN as the first conductivity type rod-shaped semiconductor. Then, an active layer 122 made of InGaN having a thickness of 10 nm is formed. Subsequently, a second conductivity type semiconductor layer 123 made of p-type GaN having a thickness of 150 nm is formed on the active layer 122 made of InGaN (semiconductor shell formation step). Further, a transparent electrode layer 124 made of 150 nm ITO is formed on the second conductivity type semiconductor layer 123 made of p-type GaN. The active layer 122 made of InGaN and the second conductivity type semiconductor layer 123 made of p-type GaN are formed by MOCVD. The transparent electrode layer 124 made of ITO is formed by sputtering, mist CVD, or plating.

  Next, as shown in FIG. 6, a first n-type GaN layer covered with an active layer 122 made of InGaN, a second conductivity type semiconductor layer 123 made of p-type GaN, and a transparent electrode layer 124 made of ITO. A gap between the conductive rod-shaped semiconductors 121 is filled with a transparent member 131 made of a silicon oxide film. The silicon oxide film can be formed by applying SOG (Spin-On Glass). After applying the SOG, the upper portion of the transparent electrode layer 124 is exposed by wet etching, and the upper electrode 141 made of ITO is formed by sputtering to complete the light emitting device 100.

  The method for manufacturing the light emitting device 100 includes a step of patterning a mask layer made of a photoresist 151 on the surface of the n-type GaN semiconductor layer 112 constituting a part or all of the first substrate 110, and the mask layer as a mask. A semiconductor core forming step of forming a plurality of n-type GaN rod-shaped semiconductors 121 by anisotropically etching the n-type GaN semiconductor layer, and covering the surface of the n-type GaN rod-shaped semiconductors 121 a semiconductor shell forming step of forming a p-type GaN semiconductor layer 123.

  With this manufacturing method, since the p-type semiconductor layer 123 is formed so as to cover the rod-shaped semiconductor 121 made of n-type GaN, almost all side surfaces of the rod-shaped semiconductor 121 emit light. Therefore, the light emission amount per area of the substrate 111 can be increased as compared with a light emitting diode chip having a planar light emitting layer. Further, according to this manufacturing method, the rod-shaped semiconductor 121 is made of an n-type semiconductor, and the resistance can be easily reduced by increasing the amount of impurities giving the n-type. Therefore, even if the length L of the rod-shaped semiconductor 121 is increased, light can be emitted uniformly from the root portion to the tip portion of the rod-shaped semiconductor 121. Therefore, it is possible to further increase the light emission amount per area of the substrate 111. Furthermore, according to this manufacturing method, since the rod-shaped semiconductor 121 is formed by anisotropic etching with the photolithography process, the rod-shaped semiconductor 121 having a good shape as intended can be obtained and the yield can be improved. be able to.

  Furthermore, in the manufacturing method, it is preferable that the length L of the n-type rod-shaped semiconductor 121 is 10 times or more the thickness D. This is because the light emission amount per area of the substrate 111 can be remarkably increased. On the other hand, when the rod-shaped semiconductor is made of an active layer as in the prior art, if the value (L / D) obtained by dividing the length L of the rod-shaped semiconductor by the thickness D is 10 or more, It becomes difficult to cause the tip portion to emit light. Therefore, when the value (L / D) obtained by dividing the length L of the rod-shaped semiconductor 121 by the thickness D is 10 or more, the advantage of the low resistance and high emission intensity of this embodiment is particularly remarkable. The value obtained by dividing the length L of the rod-shaped semiconductor by the thickness D (L / D) is difficult to be 50 or more with the current technology, and the resistance of the n-type rod-shaped semiconductor 121 of the first conductivity type is difficult. Can no longer be ignored. In addition, the light emitting area (the total area of the active layer 122 in this embodiment) is preferably three times or more than the area of the n-type semiconductor layer 113 as the semiconductor base. Here, the area of the n-type semiconductor layer (semiconductor base) 113 refers to the n-type GaN rod-shaped semiconductor 121 and structures thereon (active layer 122, p-type GaN semiconductor layer 123, transparent electrode layer 124, etc.). The area of the flat semiconductor layer 113 in a state where is removed. In such a case, the amount of emitted light per substrate 111 is large, and a sufficient cost reduction effect can be obtained.

  Furthermore, in the manufacturing method, the active layer 122 made of InGaN is formed so as to cover the surface of the rod-shaped semiconductor 121 made of n-type GaN between the semiconductor core forming step and the semiconductor shell forming step. Thereby, luminous efficiency can be raised. Note that the active layer 122 may not be formed.

  Furthermore, in the manufacturing method, the transparent electrode layer 124 is formed so as to cover the p-type GaN semiconductor layer 123 after the semiconductor shell formation step. The transparent electrode layer 124 can prevent the voltage drop in the p-type GaN semiconductor layer 123 while transmitting the light emitted from the active layer 122. Therefore, light can be emitted uniformly over the entire rod-shaped semiconductor 121.

  Further, in the above manufacturing method, the transparent electrode layer 124 is formed on the p-type GaN semiconductor layer 123. However, not all the gaps between the plurality of n-type rod-shaped semiconductors 121 are filled with the transparent electrode layer 124. The transparent electrode layer 124 is thinly formed on the type GaN semiconductor layer 123, and the remaining gap (opposing gap where the transparent electrode layers 124 face each other) is filled with the transparent member 131. This is because the transparent electrode generally has poor transparency because of the presence of carriers for flowing current. Therefore, the luminous efficiency of the light emitting element can be improved by filling the gap formed by the first conductivity type rod-shaped semiconductor 121 with a silicon oxide film, a transparent resin, or the like.

(Second embodiment)
Next, 2nd Embodiment of the light emitting element of this invention is described using FIG. 7A-FIG. 7C. FIG. 7A is a cross-sectional view of the light emitting device of the second embodiment, and FIG. 7B is a plan view of the light emitting device of the second embodiment as viewed from above, and is a diagram exclusively showing the position of the plate-like semiconductor. FIG. 7C is a plan view for explaining the method for manufacturing the light emitting element of the second embodiment.

  In the light emitting device 1100 of the second embodiment, a plate-shaped semiconductor 1121 is used instead of the plurality of first conductivity type (n-type) rod-shaped (projecting) semiconductors 121 in the light emitting device 100 of the first embodiment. The point provided is different from the first embodiment. Therefore, in the second embodiment, the details of the parts common to the first embodiment are not described.

  7A and 7B, 1100 is a light emitting element, 1111 is a substrate, 1113 is an n-type semiconductor layer, 1121 is a plate (projection) semiconductor, 1122 is an active layer, 1123 is a p-type semiconductor layer, and 1124 is transparent. An electrode layer, 1311, a transparent member, and 1141, an upper electrode. The substrate 1111, the n-type semiconductor layer 1113, the plate-like semiconductor 1121, the active layer 1122, the p-type semiconductor layer 1123, the transparent electrode layer 1124, the transparent member 1131, and the upper electrode 1141 are each in the first embodiment described above. The substrate 111, the n-type semiconductor layer 113, the rod-shaped semiconductor 121, the active layer 122, the p-type semiconductor layer 123, the transparent electrode layer 124, the transparent member 131, and the upper electrode 141 described in the embodiment are manufactured using the same materials.

  The thickness of each part is, for example, that the thickness of the n-type semiconductor layer 1113 as the semiconductor base is 5 μm, the thickness D1 of the n-type semiconductor semiconductor 1121 is 1 μm, the width D2 is 5 μm, and the height L Is 20 μm, the distance P1 between the n-type plate semiconductors 1121, the distance P2 (see FIG. 7B) is 3 μm, the thickness of the active layer 1122 is 10 nm, the thickness of the p-type semiconductor layer 1123 is 150 nm, and the transparent electrode layer 1124 However, this is not restrictive.

  In the light emitting device of this embodiment, an n-type semiconductor layer 1113 forms a lower electrode (cathode), and a current is passed between the lower electrode (cathode) and the upper electrode (anode) 1141, whereby the light emitting device (light emitting device). Diode).

  In the light emitting device of this embodiment, since the p-type semiconductor layer 1123 is formed so as to cover the n-type plate semiconductor 1121, almost all the side surfaces of the plate semiconductor 1121 emit light. Therefore, the light emission amount per area of the substrate 1111 can be increased as compared with a light emitting diode chip having a planar light emitting layer.

  Further, the light emission amount per unit area of the substrate 1111 can be increased as the height L of the plate-like semiconductor 1121 is increased. In the light emitting element of this embodiment, the plate-like semiconductor 1121 is made of an n-type semiconductor, and the resistance of the plate-like semiconductor 1121 can be easily reduced by increasing the amount of impurities that give the plate-like semiconductor 1121 n-type. Therefore, even if the height L of the plate-like semiconductor 1121 is increased, light can be emitted uniformly from the root portion to the tip portion of the plate-like semiconductor 1121. Therefore, it is possible to further increase the light emission amount per area of the substrate 1111.

  In this embodiment mode, the plate-like semiconductor 1121 is used, but the advantage of being plate-like is described as follows. In general, the light emission efficiency of a light emitting element depends on the plane orientation of the light emitting layer. For example, in a GaN-based light emitting element, it is preferable to use a nonpolar plane (a-plane or m-plane) as a light-emitting surface. By using a plate-like semiconductor, if the main surface (the surface having the width of D2 in FIG. 7B) is a nonpolar surface, the overall light emission efficiency can be increased.

  In this embodiment, the active layer 1122 is formed between the n-type plate semiconductor 1121 and the p-type semiconductor layer 1123, but this is not essential. However, it is preferable to provide the active layer 1122, which can increase the light emission efficiency. Further, since the active layer 1122 is formed between the n-type plate semiconductor 1121 and the p-type semiconductor layer 1123 to a thickness of, for example, 10 nm, the light emission efficiency is good. This is because the active layer is provided to increase the recombination probability by confining bipolar carriers (holes and electrons) in a narrow range.

  Further, although the transparent electrode layer 1124 is formed on the p-type semiconductor layer 1123, this is not essential. However, it is preferable to provide the transparent electrode layer 1124, and the presence of the transparent electrode layer 1124 causes the transparent electrode layer 1124 to transmit light emitted from the active layer 1122 while causing a voltage drop in the p-type semiconductor layer 1123. Can be prevented. Therefore, light can be emitted uniformly over the entire plate-like semiconductor 1121.

  Furthermore, even when the transparent electrode layer 1124 is formed on the p-type semiconductor layer 1123, all the gaps between the plurality of n-type plate-like semiconductors 1121 are not filled with the transparent electrode layer 1124. Is preferred. That is, after forming the thin transparent electrode layer 1124 on the p-type semiconductor layer 1123, a gap between the transparent electrode layers 1124 facing each other is formed in a gap remaining between the plurality of n-type plate-like semiconductors 1121. It is preferable to fill with a transparent member 1131 made of a material having higher transparency than the transparent electrode layer 1124. The reason for this is that the transparent electrode layer 1124 generally has poor transparency due to the presence of carriers for flowing current. Therefore, the light emitting efficiency of the light emitting element can be improved by filling the gaps between the plurality of n-type plate-like semiconductors 1121 with the transparent member 1131 made of a silicon oxide film or a transparent resin.

  In the light emitting device 1100 of this embodiment, the active layer 1122, the p-type semiconductor layer 1123, and the transparent electrode layer 1124 cover the entire surfaces of the n-type plate semiconductor 1121 and the n-type semiconductor layer 1113. It is not always necessary to cover the entire surface. That is, the active layer 1122, the p-type semiconductor layer 1123, and the transparent electrode layer 1124 only need to cover at least the n-type plate-like semiconductor 1121. This is because the active layer 1122, the p-type semiconductor layer 1123, and the transparent electrode layer 1124 cover the n-type plate semiconductor 1121, so that the light emission amount per area of the substrate 1111 can be increased.

  Next, a method for manufacturing the light emitting device 1100 of the second embodiment will be described with reference to FIG. 7C. The manufacturing method of the light emitting device 1100 of the second embodiment is substantially the same as the manufacturing method of the light emitting device 100 described in the first embodiment with reference to FIGS. The only difference between the method of manufacturing the light emitting device 1100 of the second embodiment and the method of manufacturing the light emitting device 100 is that, instead of the process described in FIG. 3A in the first embodiment, as shown in FIG. When the photoresist 1151 is patterned on the semiconductor layer 1112 made of n-type GaN by a photolithography process, the pattern of the photoresist 1151 is only made rectangular.

  Since the p-type semiconductor layer 1123 is formed so as to cover the plate-like semiconductor 1121 made of n-type GaN by the manufacturing method according to the second embodiment, almost all side surfaces of the plate-like semiconductor 1121 emit light. Therefore, the light emission amount per area of the substrate 1111 can be increased as compared with a light emitting diode chip having a planar light emitting layer. Further, according to this manufacturing method, the plate-like semiconductor 1121 is made of an n-type semiconductor, and the resistance can be easily reduced by increasing the amount of impurities that give the n-type. Therefore, even if the height L of the plate-like semiconductor 1121 is increased, light can be emitted uniformly from the root portion to the tip portion of the plate-like semiconductor 1121. Therefore, it is possible to further increase the light emission amount per area of the substrate 1111. Furthermore, according to this manufacturing method, since the plate-like semiconductor 1121 is formed by anisotropic etching with the photolithography process, the plate-like semiconductor 1121 having a good shape as intended can be obtained and the yield can be increased. Can be improved.

  Further, in the manufacturing method, the active layer 122 made of InGaN is formed so as to cover the surface of the plate-like semiconductor 1121 made of n-type GaN between the semiconductor core forming step and the semiconductor shell forming step. Thereby, luminous efficiency can be raised. Note that the active layer 1122 may not be formed.

  Furthermore, in the manufacturing method, the transparent electrode layer 1124 is formed so as to cover the p-type GaN semiconductor layer 1123 after the semiconductor shell formation step. The transparent electrode layer 1124 can prevent a voltage drop in the p-type GaN semiconductor layer 1123 while transmitting light emitted from the active layer 1122. Therefore, light can be emitted uniformly over the entire plate-like semiconductor 1121.

  Further, in the above manufacturing method, the transparent electrode layer 1124 is formed on the p-type GaN semiconductor layer 1123. Instead of filling all the gaps between the plurality of n-type plate-like semiconductors 1121 with the transparent electrode layer 1124, The transparent electrode layer 1124 is thinly formed on the p-type GaN semiconductor layer 1123, and the remaining gap (opposing gap where the transparent electrode layers 1124 face each other) is filled with the transparent member 1131. This is because the transparent electrode generally has poor transparency because of the presence of carriers for flowing current. Therefore, the light emitting efficiency of the light emitting element can be improved by filling the gap formed by the first conductive type plate-like semiconductor 1121 with a silicon oxide film or a transparent resin.

  In the second embodiment and the first embodiment described above, the rod-shaped semiconductor 121 and the plate-shaped semiconductor 1121 are used, but the shape of these semiconductors is not limited to this. It is essential that a first conductive type protruding semiconductor is formed on a first conductive type semiconductor layer serving as a semiconductor base, and that the first conductive type protruding semiconductor is covered with the second conductive type. Important. Therefore, the protruding semiconductor of the first conductivity type is not limited to the rod shape or the plate shape, but may be a bent plate shape or an annular shape (tubular shape) in which the plate semiconductor is closed. Further, in the protruding semiconductor of the present invention, the plate-shaped semiconductors arranged in two directions may be connected to each other at the intersection to form one lattice-shaped protruding semiconductor. It may be a shape, a polygonal column shape, a conical shape, a polygonal pyramid shape, a hemispherical shape, a spherical shape, or the like.

(Third embodiment)
Next, a method for manufacturing a light emitting element and a light emitting device as a third embodiment of the present invention will be described with reference to FIGS. 8-17 is a figure which shows the process of forming a light emitting element and a light-emitting device by this 3rd Embodiment.

  In the manufacturing method of the third embodiment, the first half of the process is the same as the manufacturing process described with reference to FIGS. 2 to 5 in the first embodiment. Therefore, here, the manufacturing process from FIG. 2 to FIG. 5 described above will be described following the process from FIG. 2 to FIG. The first half of the manufacturing method according to the third embodiment is the same as the process described with reference to FIG. 3A in the steps of FIGS. Instead of the steps described above, the first conductive type protruding semiconductor may be a plate semiconductor.

  In the process described above with reference to FIG. 5, the active layer 122 made of InGaN, the second conductive type semiconductor layer 123 made of p-type GaN, and the transparent electrode made of ITO are sequentially formed on the surface of the n-type GaN rod-shaped semiconductor 121. Layer 124 is deposited. Thereafter, anisotropic dry etching is performed. By this anisotropic dry etching, as shown in FIG. 8, the transparent electrode layer 124 made of ITO, the second conductive type semiconductor layer 123 made of p-type GaN, the active layer 122 made of InGaN, and the first layer made of GaN. Part of each of the one-conductivity-type rod-shaped semiconductor 121 and the first-conductivity-type semiconductor layer 113 made of n-type GaN is removed to expose part of the substrate 111 made of silicon. As a result, the InGaN active layer 122, the p-type GaN semiconductor layer 123, and the ITO transparent electrode layer 124 are left on the side wall of the remaining portion of the rod-shaped semiconductor 121 made of n-type GaN. The semiconductor layer 113 made of n-type GaN becomes a plurality of n-type GaN semiconductor layers 125 spaced from each other on the silicon substrate 111. Then, one n-type GaN rod-shaped semiconductor 121 is erected on each n-type GaN semiconductor layer 125, and this n-type GaN semiconductor layer 125, n-type GaN rod-shaped semiconductor 121, InGaN active layer 122, p-type GaN. A plurality of portions Z each including the semiconductor layer 123 and the ITO transparent electrode layer 124 are erected on the silicon substrate 111 at intervals.

  Next, as shown in FIG. 9, the plurality of portions Z protruding on the surface of the silicon substrate 111 are separated from the silicon substrate 111 (light emitting element separation step). At this time, in FIG. 2, the n-type GaN semiconductor layer 112 forming a part of the first substrate 110 has an upper structure (n-type GaN rod-shaped semiconductor 121, n-type GaN semiconductor layer 125). Used for formation. Therefore, the silicon substrate 111 is synonymous with the first substrate 110.

  As shown in FIG. 9, each of the plurality of separated portions Z becomes a light emitting element 200. The n-type GaN semiconductor layer 125 is exposed on the side of the light emitting element 200 that is in contact with the silicon substrate 111, and the side that is separated from the silicon substrate 111 is in electrical contact with the p-type GaN semiconductor layer 123. The transparent electrode layer 124 made of ITO is exposed. The n-type GaN semiconductor layer 125 becomes the cathode electrode K, and the transparent electrode layer 124 becomes the anode electrode A. In this separation step, for example, the rod-shaped portion Z is cut from the silicon substrate 111 by irradiating ultrasonic waves in the solution to vibrate the rod-shaped portion Z. When the first conductive type protruding semiconductor is a plate-like semiconductor, the light-emitting element separated in this way is also plate-like. However, since the following steps are the same for the plate-like light emitting element, the following description will be made assuming that the light emitting element is rod-shaped exclusively.

  The manufacturing method of the third embodiment is a process of patterning a mask layer with a photoresist 151 on the surface of the n-type semiconductor layer 112 forming a part of the first substrate 110 described with reference to FIGS. A step of forming a semiconductor core by anisotropically etching the n-type semiconductor layer 112 using the mask layer as a mask to form a plurality of n-type rod-shaped semiconductors 121; and a surface of the n-type rod-shaped semiconductor 121 A semiconductor shell forming step of forming a p-type semiconductor layer 123 so as to cover it. Note that the entire first substrate 110 may be formed of the n-type semiconductor layer 112.

  In addition to this, the manufacturing method of the third embodiment is a light emitting device that separates the n-type rod-shaped semiconductor 121 covered with the p-type semiconductor layer 123 from the first substrate 110, as described in FIGS. A separation process is provided. According to these steps, the rod-like light emitting element 200 formed by processing the n-type GaN semiconductor layer 112 finally becomes an independent light emitting element.

  Therefore, the light emitting element utilization methods can be diversified and the utility value can be increased in that each light emitting element 200 can be used individually. For example, a desired number of separated light emitting elements 200 can be arranged at a desired density. In this case, for example, a surface light-emitting device can be configured by rearranging a large number of fine light-emitting elements 200 on a large-area substrate. In addition, the heat generation density can be lowered to achieve high reliability and long life. In addition, since the p-type semiconductor layer 123 is formed so as to cover the n-type rod-shaped semiconductor 121 by this manufacturing method, almost all side surfaces of the rod-shaped semiconductor 121 emit light. Therefore, a large number of light emitting elements 200 having a large total light emission amount can be obtained from the substrate 111 (first substrate 110) having a small area. Further, according to this manufacturing method, the rod-shaped semiconductor 121 is made of an n-type semiconductor, and the resistance can be easily reduced by increasing the amount of impurities giving the n-type.

  Therefore, even if the length L of the rod-shaped semiconductor 121 is increased, light can be emitted uniformly from the root portion to the tip portion of the rod-shaped semiconductor 121. Furthermore, according to this manufacturing method, since the rod-shaped semiconductor 121 is formed by anisotropic etching with the photolithography process, a desired-shaped rod-shaped semiconductor 121 is obtained as intended, and thus desired good A light-emitting element 200 having a simple shape can be obtained. Therefore, the yield of the light emitting element 200 can be improved.

  Furthermore, in the manufacturing method, since the active layer 122 is formed so as to cover the surface of the n-type rod-shaped semiconductor 121 between the semiconductor core forming step and the semiconductor shell forming step, the luminous efficiency can be increased. Note that the active layer 122 may not be formed.

  Furthermore, in the manufacturing method, since the transparent electrode layer 124 is formed so as to cover the p-type semiconductor layer 123 after the semiconductor shell forming step, the p-type semiconductor is transmitted while transmitting the light emitted from the active layer 122. It is possible to prevent a voltage drop from occurring in the layer 123. Therefore, light can be emitted uniformly over the entire rod-shaped semiconductor 121.

  Next, with reference to FIGS. 10 to 17 in sequence, a process of arranging and wiring the light emitting element 200 separated from the silicon substrate 111 (first substrate 110) on the second substrate 210 will be described.

  First, as shown in FIG. 10, a second substrate 210 having a surface on which a first electrode 211 and a second electrode 212 are formed is prepared. The second substrate 210 is an insulating substrate, and the first and second electrodes 211 and 212 are metal electrodes. As an example, a metal electrode having a desired electrode shape can be formed on the surface of the second substrate 210 as the first and second electrodes 211 and 212 using a printing technique. Further, a metal film and a photoreceptor film are uniformly deposited on the surface of the second substrate 210, the photoreceptor film is exposed and developed to a desired electrode pattern, and the metal film is formed using the patterned photoreceptor film as a mask. The first and second electrodes 211 and 212 can be formed by etching.

  As the metal material for forming the first and second electrodes 211 and 212, gold, silver, copper, tungsten, aluminum, tantalum, or an alloy thereof can be used. The second substrate 210 is an insulating material such as glass, ceramic, alumina, or resin, or a silicon oxide film formed on a semiconductor surface such as silicon, and the surface is insulative. In the case where a glass substrate is used as the second substrate 210, a base insulating film such as a silicon oxide film or a silicon nitride film is preferably formed on the surface.

  The surfaces of the first and second electrodes 211 and 212 may be covered with an insulating film (not shown). In this case, the following effects are produced. In the subsequent fine object arranging step, a voltage is applied between the first electrode 211 and the second electrode 212 in a state where the liquid is introduced onto the second substrate 210. Current can be prevented from flowing. Such a current can cause a voltage drop in the electrode and cause alignment failure, or can cause the electrode to dissolve due to electrochemical effects. As the insulating film covering the first and second electrodes 211 and 212, for example, a silicon oxide film or a silicon nitride film can be used. On the other hand, when not covered with such an insulating film, the first and second electrodes 211 and 212 and the light emitting element 200 can be easily electrically connected, so that the first and second electrodes 211 and 212 are used as wirings. Easy to use.

  The place where the light emitting element 200 is disposed is defined by the place S where the facing portion 211A of the first electrode 211 and the facing portion 212A of the second electrode 212 face each other. That is, in the light emitting element disposition process described later, the light emitting element 200 is disposed at a location S where the first and second electrodes 211 and 212 face each other so as to bridge the first and second electrodes 211 and 212. . For this reason, the distance between the first electrode 211 and the second electrode 212 in the place S where the facing portions 211A and 212A of the first and second electrodes 211 and 212 face each other is slightly shorter than the length of the light emitting element 200. Is desirable. As an example, when the light emitting element 200 has a long and narrow strip shape, and the length of the light emitting element 200 is 20 μm, the distance between the facing portion 211A of the first electrode 211 and the facing portion 212A of the second electrode 212 is It is desirable to set it as 12 micrometers-18 micrometers. That is, the distance is preferably about 60 to 90% of the length of the light emitting element 200, more preferably about 80 to 90% of the length of the light emitting element 200.

  Next, as illustrated in FIG. 11, a fluid 221 including a plurality of light emitting elements 200 is introduced onto the second substrate 210. The plurality of light emitting elements 200 are dispersed in the fluid 221. Note that FIG. 11 shows a cross section of the second substrate 210 taken along line VV in FIG.

  The fluid 221 may be a liquid such as IPA (isopropyl alcohol), ethanol, methanol, ethylene glycol, propylene glycol, acetone, water, or a mixture thereof, but is not limited thereto. However, as preferable properties that the fluid 221 should have, the viscosity is low so as not to disturb the arrangement of the light-emitting elements, the ion concentration is not extremely high, and the substrate is volatile so that the substrate can be dried after the arrangement of the light-emitting elements. It is. When a liquid having a remarkably high ion concentration is used, when a voltage is applied to the first and second electrodes 211 and 212, an electric double layer is quickly formed on the electrodes and the electric field penetrates into the liquid. Therefore, the arrangement of the light emitting elements is hindered.

  Although not shown, it is preferable to provide a cover on the second substrate 210 so as to face the second substrate 210. The cover is installed in parallel with the second substrate 210, and a uniform gap (for example, 500 μm) is provided between the second substrate 210 and the cover. A fluid 221 including the light emitting element 200 is filled in the gap. By doing so, it becomes possible to flow a fluid at a uniform speed in the channel due to the gap in the fine object arranging step described below, and a plurality of light emitting elements 200 are arranged uniformly on the second substrate 210. It becomes possible to do. Further, it is possible to prevent the fluid 221 from evaporating and causing convection and disturbing the arrangement of the light emitting elements 200 in the next fine object arranging step.

  Next, a voltage having a waveform as shown in FIG. 12 is applied between the first electrode 211 and the second electrode 212. As a result, as shown in the plan view of FIG. 13 and the cross-sectional view of FIG. The light emitting element 200 is arranged at a predetermined position on the second substrate 210 (light emitting element arrangement step). FIG. 14 is a cross-sectional view taken along line VV in FIG.

The principle that the light emitting element 200 is arranged at a predetermined position on the second substrate 210 will be described as follows. An alternating voltage as shown in FIG. 12 is applied between the first electrode 211 and the second electrode 212. The reference potential _{V R} shown in Figure 12 to the second electrode 212 is applied, the first electrode 211 applies an AC voltage of amplitude VPPL / 2. When a voltage is applied between the first electrode 211 and the second electrode 212, an electric field is generated in the fluid 221. By this electric field, polarization occurs in the light emitting element 220 or charges are induced, and charges are induced on the surface of the light emitting element 220. Due to the induced electric charge, an attractive force acts between the first and second electrodes 211 and 212 and the light emitting element 200. Actually, in order for dielectrophoresis to occur, an electric field gradient needs to exist around the object, and dielectrophoresis does not work on an object that exists in an infinitely large parallel plate, but with an electrode arrangement as shown in FIG. Since the electric field is stronger as it is closer to the electrode, dielectrophoresis occurs.

  Note that when the light emitting element arranging step is performed by the above method, the direction (polarity) of the light emitting element 200 is random as shown in FIG. Here, the direction (polarity) of the light emitting element 200 is the direction in which the anode A of the light emitting element 200 is on the right side of the cathode K and the anode A of the light emitting element 200 is on the left side of the cathode K in FIG. Say which direction it is. In addition, an appropriate operation method of the light emitting device in which the directions of the plurality of light emitting elements 200 are randomly arranged will be described later.

  When IPA is used as the fluid 221, the frequency of the AC voltage applied to the first electrode 211 is preferably 10 Hz to 1 MHz, and more preferably 50 Hz to 1 kHz because the arrangement is most stable. Furthermore, the AC voltage applied between the first electrode 211 and the second electrode 212 is not limited to a sine wave, but may be any one that periodically varies, such as a rectangular wave, a triangular wave, and a sawtooth wave. The VPPL, which is twice the amplitude of the AC voltage applied to the first electrode 211, can be set to 0.1 to 10 V. However, when the voltage is 0.1 V or less, the arrangement of the light emitting elements 200 is deteriorated. Immediately fixed on the substrate 110, the yield of the arrangement deteriorates. Therefore, the VPPL is preferably 1 to 5V, and more preferably about 1V.

  Next, as shown in FIG. 15, after the arrangement of the light emitting element 200 on the second substrate 210 is completed, the AC voltage is applied between the first electrode 211 and the second electrode 212. Thus, by heating the second substrate 210, the liquid of the fluid 221 is evaporated and dried, and the light emitting element 200 is fixed onto the second substrate 210. Alternatively, after the arrangement of the light emitting element 200 on the second substrate 210 is completed, a sufficiently high voltage (10 to 100 V) is applied to the first electrode 211 and the second electrode 212 to thereby form the light emitting element 200. The second substrate 210 is dried after being fixed on the second substrate 210 and the application of the high voltage is stopped.

  Next, as shown in FIG. 16, an interlayer insulating film 213 made of a silicon oxide film is deposited on the entire surface of the second substrate.

  Next, as shown in FIG. 17, a contact hole 217 is formed in the interlayer insulating film 213 by applying a general photolithography process and a dry etching process, and further a metal is deposited by a metal deposition process, a photolithography process, and an etching process. Are patterned to form metal wirings 214 and 215 (light emitting element wiring step). Thereby, the anode A and the cathode K of the light emitting element 200 can be wired respectively. Thus, the light emitting device 250 is completed.

  As described above, in the manufacturing method of the third embodiment, the photoresist 151 is formed on the surface of the n-type semiconductor layer 112 constituting part or all of the first substrate 110 described with reference to FIGS. A step of patterning the mask layer, a step of forming a semiconductor core in which the n-type semiconductor layer 112 is anisotropically etched using the mask layer as a mask to form a plurality of n-type rod-shaped semiconductors 121; A semiconductor shell forming step of forming a p-type semiconductor layer 123 so as to cover the surface of the rod-shaped semiconductor 121. Furthermore, in the manufacturing method of the third embodiment, the light emitting element that separates the n-type rod-shaped semiconductor 121 covered with the p-type semiconductor layer 123 from the first substrate 110 described with reference to FIGS. A separation process is provided. In addition to this, a light emitting element arrangement step of arranging an n-type rod-shaped semiconductor 121 covered with a p-type semiconductor layer 123 separated from the silicon substrate 111 of the first substrate 110 on the second substrate 210; And a light emitting element wiring step of performing wirings 214 and 215 for energizing the n-type rod-shaped semiconductor 121 covered with the p-type semiconductor layer 123 disposed on the second substrate 210.

  According to such a manufacturing process, a desired number of the separated light emitting elements 200 can be arranged on the second substrate 210 at a desired density. Therefore, for example, a surface light emitting device can be configured by rearranging a number of fine light emitting elements 200 on the second substrate 210 having a large area. In addition, the heat generation density can be lowered to achieve high reliability and long life.

  As described above, when the light emitting element arranging step is performed, as shown in FIG. 13, the direction of the light emitting element 200 (that is, the anode A is located on the right side or the left side of the cathode K in FIG. 13). Was random). In such a case, of course, a DC voltage may be applied between the two metal wirings 214 and 215. In this case, however, a reverse voltage is applied to about half of the light emitting elements 200 and no light is emitted. Therefore, it is preferable to apply an AC voltage between the two metal wirings 214 and 215. In this way, all the light emitting elements 200 can emit light.

(Fourth embodiment)
Next, with reference to FIGS. 18-21, the illuminating device provided with the light-emitting device formed using the manufacturing method of the light-emitting device of this invention is demonstrated as 3rd Embodiment of this invention.

  FIG. 18 is a side view of an LED bulb 300 that is the illumination device of the fourth embodiment. This LED bulb 300 has a base 301 as a power supply connection part that is fitted in an external socket and connected to a commercial power supply, and a conical heat dissipation part that has one end connected to the base 301 and the other end gradually expanding in diameter. 302 and a translucent part 303 that covers the other end of the heat dissipating part 302. A light emitting unit 304 is disposed in the heat radiating unit 302.

  As shown in the side view of FIG. 19 and the top view of FIG. 20, the light emitting unit 304 has a light emitting device 306 in which a large number of light emitting elements are arranged on a square heat sink 305. As shown in FIG. 21, the light emitting device 306 includes a substrate 310, a first electrode 311 and a second electrode 312 formed on the substrate 310, and a large number of light emitting elements 320. The method described in the third embodiment described above may be used as a method for arranging a fine light emitting element (light emitting diode) 320 on the substrate 310 and a method for wiring. That is, the light emitting device 306 is manufactured by the method described in the third embodiment.

  In FIG. 21, although 27 light emitting elements 320 are illustrated, a larger number of light emitting elements can be arranged. For example, the size of one light emitting element 320 is 20 μm in length and 1 μm in diameter as exemplified in the second embodiment, and the luminous flux emitted from one light emitting element 320 is 5 millimeters. Thousand light-emitting elements 320 can be arranged on the substrate 310 to form a light-emitting substrate that emits a total of 250 lumens.

As described above, when the light emitting device 306 in which a large number of light emitting elements 320 are arranged on the substrate 310 is used, the following effects can be obtained as compared with the case of using a light emitting device in which one or several light emitting elements are arranged. . First, since the light emitting area of each light emitting element 320 is small and they are dispersed on the substrate 310, the heat generation density associated with light emission is small and uniform. On the other hand, since a normal light emitting element (light emitting diode) has a large light emitting area (may reach 1 mm ² ), the heat generation density associated with light emission is large, and the light emitting layer becomes hot, affecting the light emission efficiency and reliability. Is given. As in the third embodiment, by arranging a large number of fine light emitting elements 320 on the substrate 310 of the light emitting device 306, the light emission efficiency can be improved and the reliability can be improved.

(Fifth embodiment)
FIG. 22 is a plan view showing a backlight as a fifth embodiment of the present invention. The fifth embodiment includes a light emitting device manufactured by the method for manufacturing a light emitting device of the present invention as described in the above third embodiment.

  In the backlight 400 of the fifth embodiment, as shown in FIG. 22, a plurality of light emitting devices 402 are mounted in a grid pattern at predetermined intervals on a rectangular support substrate 401 as an example of a heat sink. Has been. Here, the light emitting device 402 is a light emitting device manufactured using the method for manufacturing a light emitting device of the second embodiment described above. In the light emitting device 402, 100 or more light emitting elements are arranged on a substrate (not shown).

  According to the backlight having the above structure, by using the light-emitting device 402, it is possible to realize a backlight that has little variation in brightness and can achieve long life and high efficiency. Further, by attaching the light emitting device 402 on the support substrate 401, the heat dissipation effect is further improved.

(Sixth embodiment)
Next, with reference to FIG. 23, the LED display as 6th Embodiment of this invention is demonstrated. The sixth embodiment relates to a display device manufactured using a method similar to the method for manufacturing a light emitting device of the present invention.

  FIG. 23 shows a circuit of one pixel of the LED display as the sixth embodiment. This LED display is manufactured using the manufacturing method of the light emitting element or the light emitting device of the present invention. As the light emitting element included in the LED display, the light emitting element 200 described in the third embodiment can be used.

  This LED display is of an active matrix address system, a selection voltage pulse is supplied to the row address line X1, and a data signal is sent to the column address line Y1. When the selection voltage pulse is input to the gate of the transistor T1 and the transistor T1 is turned on, the data signal is transmitted from the source to the drain of the transistor T1, and the data signal is stored as a voltage in the capacitor C. The transistor T2 is for driving the pixel LED 520, and the light emitting element 200 described in the third embodiment can be used for the pixel LED 20.

  The pixel LED 520 is connected to the power source Vs through the transistor T2. Therefore, when the transistor T2 is turned on by the data signal from the transistor T1, the pixel LED 520 is driven by the power source Vs.

  In the LED display of this embodiment, one pixel shown in FIG. 23 is arranged in a matrix. A pixel LED 520 and transistors T1 and T2 of each pixel arranged in a matrix are formed on the substrate.

  In order to produce the LED display of this embodiment, for example, the following steps may be performed.

  First, the light emitting device 200 is formed by the semiconductor core forming step, the semiconductor shell forming step, and the light emitting device separating step described with reference to FIGS. 2 to 5, 8, and 9 in the manufacturing method of the third embodiment. To do. Next, the transistors T1 and T2 are formed on a substrate such as glass using a normal TFT forming method. Next, a first electrode and a second electrode for arranging minute light-emitting elements to be the pixel LEDs 520 are formed on the substrate on which the TFT is formed. Next, by using the method described with reference to FIGS. 10 to 16 in the third embodiment, a minute light emitting element 200 is disposed at a predetermined position on the substrate (light emitting element arranging step). Thereafter, an upper wiring process is performed to connect the minute light emitting element 200 to the drain of the transistor T2 and the ground line (light emitting element wiring process).

  That is, the above manufacturing process is performed on the surface of the n-type semiconductor layer 112 constituting a part or the whole of the first substrate 110 as described in the third embodiment with reference to FIGS. A step of patterning a mask layer with a resist 151; a step of forming a semiconductor core in which the n-type semiconductor layer 112 is anisotropically etched using the mask layer as a mask to form a plurality of n-type rod-shaped semiconductors 121; a semiconductor shell forming step of forming a p-type semiconductor layer 123 so as to cover the surface of the n-type rod-shaped semiconductor 121. Further, in the manufacturing process, the n-type rod-shaped semiconductor 121 covered with the p-type semiconductor layer 123 described in the third embodiment with reference to FIGS. 8 and 9 is separated from the first substrate 110. A light emitting element separating step; In addition, in the manufacturing process, the n-type rod-shaped semiconductor 121 covered with the p-type semiconductor layer 123 separated from the silicon substrate 111 of the first substrate 110 is placed at the pixel position on the second substrate. Corresponding light emitting element arranging steps and wiring for energizing the n-type rod-shaped semiconductor 121 covered with the p-type semiconductor layer 123 arranged corresponding to the pixel position on the second substrate. And a light emitting element wiring step to be performed.

  According to the manufacturing process described above, since the p-type semiconductor layer 123 is formed so as to cover the surface of the n-type rod-shaped semiconductor 121, the light emission area per unit area of the first substrate 110 is very large. , And 10 times that in the case of planar epitaxial growth. In order to obtain the same light emission amount, the number of substrates can be reduced to, for example, 1/10, and the manufacturing cost can be greatly reduced. That is, the manufacturing cost of the n-type rod-shaped semiconductor 121 covered with the p-type semiconductor layer 123 functioning as a light-emitting element can be greatly reduced. Then, the n-type rod-shaped semiconductor 121 covered with the p-type semiconductor layer 123 is separated from the silicon substrate 111 of the first substrate 110, and is disposed on the second substrate that becomes the panel of the display device of this embodiment. Further, the display device is manufactured by wiring. Since the number of pixels of the display device of this embodiment is about 6 million, for example, when a light emitting element is used for each pixel, the cost of the light emitting element is extremely important. Therefore, manufacturing the display device through the above steps can reduce the manufacturing cost of the display device.

  In the method of arranging the light emitting element 200 as the pixel LED 520 in this embodiment on the second substrate (see FIGS. 10 to 16), the orientation of the anode and the cathode of the pixel LED 520 is random. Is AC driven.

  In the above description, as an example, the case where the semiconductor layer 113 as the first conductivity type semiconductor base and the first conductivity type rod-shaped semiconductor 121 are n-type and the second conductivity type semiconductor layer 123 is p-type. As described above, the semiconductor layer 113 as the first conductivity type semiconductor base and the first conductivity type rod-shaped semiconductor 121 may be p-type, and the second conductivity type semiconductor layer 123 may be n-type.

100 light emitting element 110 first substrate 111 silicon substrate 112 n-type GaN semiconductor layer 113 n-type GaN semiconductor layer 121 n-type GaN rod-shaped semiconductor 122 active layer 123 p-type GaN semiconductor layer 124 transparent electrode layer 125 n-type GaN semiconductor layer 131 transparent Member 141 Upper electrode 151 Photoresist A Anode K Cathode 200 Rod-like light emitting element 210 Second substrate 211 First electrode 211A Opposing portion 212 Second electrode 212A Opposing portion 213 Interlayer insulating films 214 and 215 Metal wiring 221 Fluid 300 LED Light bulb 301 Base 302 Heat radiating part 304 Light emitting part 305 Heat radiating plate 306 Light emitting device 310 Substrate 311 First electrode 312 Second electrode 320 Light emitting element 400 Back light 401 Support substrate 402 Light emitting device 520 Pixel LED
X1 row address line Y1 column address line 1100 light emitting element 1111 substrate 1113 n-type semiconductor layer 1121 plate-like (projection-like) semiconductor 1122 active layer 1123 p-type semiconductor layer 1124 transparent electrode layer 1131 transparent member 1141 upper electrode 1151 photoresist

Claims (15)

A first conductivity type semiconductor base;
A plurality of first-conductivity-type protruding compound semiconductors formed to project and extend on the first-conductivity-type semiconductor base;
A second conductive type compound semiconductor layer serving as a shell covering at least the side surface of the protruding compound semiconductor;
While light is emitted between the side surface of the first conductive type protruding compound semiconductor and the second conductive type compound semiconductor layer,
E Bei transparent electrode layer <br/> covering the side surface of the shell to become the second conductive type compound semiconductor layer which covers the protruding compound semiconductor side surface of the first conductivity type,
The first conductive type protruding compound semiconductor is a first conductive type plate compound semiconductor;
The plate compound semiconductor of the first conductivity type has a rectangular cross section, and a light emitting surface in which a side surface on the long side of the plate compound semiconductor having a rectangular cross section is a nonpolar surface . The light emitting device according to claim 1,
An active layer is formed between the first conductive type protruding compound semiconductor and the second conductive type compound semiconductor layer. The light emitting device according to claim 1 or 2,
The protruding compound semiconductor of the first conductivity type is an n-type protruding compound semiconductor,
The light emitting element, wherein the second conductive type compound semiconductor layer is a p-type compound semiconductor layer. In the light emitting element as described in any one of Claim 1 to 3,
A transparent member made of a material having higher transparency than the transparent electrode layer is filled in a facing gap where the transparent electrode layer is opposed between the plurality of first conductive type protruding compound semiconductors. A light emitting device characterized by the above. Patterning a mask layer on the surface of the first conductive type compound semiconductor layer forming part or all of the first substrate;
Semiconductor forming the protruding compound semiconductor side surface of the mask layer and anisotropically dry etching the compound semiconductor layer as a mask to extending protrusion of the first conductivity type of a plurality of the etched surface by the dry etching A core forming step;
E Bei a semiconductor shell formation step for forming a compound semiconductor layer of a second conductivity type comprising a shell so as to cover the whole of the protruding compound semiconductor side surface of the first conductivity type,
After the semiconductor core forming step and before the semiconductor shell forming step, a crystal defect recovery step of annealing the first conductive type protruding compound semiconductor is performed,
Producing a light emitting element that emits light between the side surface of the protruding conductive compound semiconductor of the first conductive type and the second conductive type compound semiconductor layer serving as a shell covering the side surface. Manufacturing method of light emitting element. Patterning a mask layer on the surface of the first conductive type compound semiconductor layer forming part or all of the first substrate;
Semiconductor forming the protruding compound semiconductor side surface of the mask layer and anisotropically dry etching the compound semiconductor layer as a mask to extending protrusion of the first conductivity type of a plurality of the etched surface by the dry etching A core forming step;
E Bei a semiconductor shell formation step for forming a compound semiconductor layer of a second conductivity type comprising a shell so as to cover the whole of the protruding compound semiconductor side surface of the first conductivity type,
After the semiconductor core formation step and before the shell formation step, a crystal defect removal step is performed to etch the side surfaces of the protruding compound semiconductors protruding and extending of the first conductivity type by wet etching,
Producing a light emitting element that emits light between the side surface of the protruding conductive compound semiconductor of the first conductive type and the second conductive type compound semiconductor layer serving as a shell covering the side surface. Manufacturing method of light emitting element. Patterning a mask layer on the surface of the first conductive type compound semiconductor layer forming part or all of the first substrate;
Semiconductor forming the protruding compound semiconductor side surface of the mask layer and anisotropically dry etching the compound semiconductor layer as a mask to extending protrusion of the first conductivity type of a plurality of the etched surface by the dry etching A core forming step;
E Bei a semiconductor shell formation step for forming a compound semiconductor layer of a second conductivity type comprising a shell so as to cover the whole of the protruding compound semiconductor side surface of the first conductivity type,
A crystal defect removing step of etching a side surface of the protruding compound semiconductor extending and extending of the first conductivity type by wet etching after the semiconductor core forming step and before the shell forming step;
A crystal defect recovery step of annealing the first conductive type protruding compound semiconductor after the semiconductor core formation step and before the semiconductor shell formation step ;
In the order of the crystal defect removal step, the crystal defect recovery step,
Producing a light emitting element that emits light between the side surface of the protruding conductive compound semiconductor of the first conductive type and the second conductive type compound semiconductor layer serving as a shell covering the side surface. Manufacturing method of light emitting element. In the manufacturing method of the light emitting element as described in any one of Claim 5 to 7,
A light emitting element separating step of separating the first conductive type protruding compound semiconductor covered with the compound semiconductor layer serving as the second conductive type shell from the first substrate; Production method. A method for manufacturing a light emitting device according to any one of claims 5 to 8 ,
An active layer is formed between the semiconductor core formation step and the semiconductor shell formation step so as to cover the surface of the protruding compound semiconductor that protrudes and extends of the first conductivity type. Production method. A method for manufacturing a light emitting device according to any one of claims 5 to 9 ,
After the semiconductor shell formation step, a transparent electrode layer is formed so as to cover the side surface of the second conductivity type compound semiconductor layer. By the manufacturing method of a light emitting device according to claim 8, the second conductive type compound semiconductor layer covered with the first conductive protruding compound semiconductor formed with the shell separately from the first substrate, the Obtaining a light emitting element that emits light between the side surface of the first conductive type protruding compound semiconductor and the second conductive type compound semiconductor layer covering the side surface ,
A light emitting element disposing step of disposing the light emitting element on the second substrate;
A light-emitting device manufacturing method comprising: a light-emitting element wiring step for performing wiring for energizing the light-emitting elements disposed on the second substrate. An illumination device comprising the light emitting device manufactured by the method for manufacturing a light emitting device according to claim 11 . A liquid crystal backlight comprising the light emitting device manufactured by the method for manufacturing a light emitting device according to claim 11 . By the manufacturing method of a light emitting device according to claim 8, the second conductive type compound semiconductor layer covered with the first conductive protruding compound semiconductor formed with the shell separately from the first substrate, the Obtaining a light emitting element that emits light between the side surface of the first conductive type protruding compound semiconductor and the second conductive type compound semiconductor layer covering the side surface ,
A light emitting element arranging step of arranging the light emitting element corresponding to a pixel position on the second substrate;
A method of manufacturing a display device, comprising: a light emitting element wiring step for performing wiring for energizing light emitting elements arranged corresponding to pixel positions on the second substrate. A display device manufactured by the method for manufacturing a display device according to claim 14 .

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