JP5755510B2 - Semiconductor light emitting device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a semiconductor light emitting device and a method for manufacturing the same. The present invention particularly relates to a semiconductor light-emitting device having two light-emitting layers having the same emission peak wavelength, and a semiconductor light-emitting device capable of obtaining a high maximum current value and a light-emission output with a low forward voltage, and its manufacture Regarding the method.

  In recent years, along with diversification of uses of light-emitting diodes (LEDs) such as application to headlamps, brake lamps, and traffic lights of automobiles, improvement in light output of LEDs has been demanded.

  In general, an LED is a semiconductor light emitting device having a structure including a p-type semiconductor layer, an n-type semiconductor layer, and a light emitting layer provided between these semiconductor layers between a front electrode and a back electrode. High quality LEDs are generally required to have high output, low power consumption (low forward voltage), and long life. The light emission output in the light emitting layer increases as the current density flowing in the light emitting layer is increased. However, an excessive current density generates heat from the light emitting layer, causing a decrease in light emission output and shortening the life of the LED. Therefore, there is an upper limit (maximum current value) in the current value that can be passed through the LED. . Therefore, there is a need for an LED that balances all of the high maximum current value, high light emission output, and low forward voltage in a well-balanced manner.

  Here, Patent Document 1 describes an LED having two element structures in which two light emitting layers having similar or different emission wavelengths are arranged vertically to emit incoherent light. First, a semiconductor light-emitting element in which an n-type semiconductor layer, a first light-emitting layer, a p-type semiconductor layer, an n-type semiconductor layer, a second light-emitting layer, and a p-type semiconductor layer are sequentially formed between a front electrode and a back electrode. It is. This semiconductor light emitting element suggests that a high output is obtained by using a tunnel junction formed in a pn junction between the first and second light emitting layers (see FIG. 1 of Patent Document 1). Second, a first n-type semiconductor layer, a first light-emitting layer, a p-type semiconductor layer, a second light-emitting layer, and a second n-type semiconductor layer are sequentially formed between the front electrode and the back electrode, and a second n-type semiconductor layer is formed. And a semiconductor light emitting device in which a reference electrode in contact with the p-type semiconductor layer is provided in a recess penetrating the second light emitting layer, and the light emitting layer has a pn-np structure or an np-pn structure. This semiconductor light emitting element is an element in which current flows from a reference electrode to a back electrode via a first light emitting layer and to a front electrode via a second light emitting layer (see FIG. 2 of Patent Document 1). .

  Patent Document 2 describes an LED that emits light of different wavelengths by vertically combining light emitting layers made of different materials.

Special table 2009-522755 JP-A-55-148477

  The present inventors have made various studies in order to improve characteristics such as the maximum current value, light emission output, and forward voltage of an LED having a predetermined emission peak wavelength. Here, when the LED having a large chip size, that is, the LED having a large light emitting layer area viewed from the vertical direction when the vertical direction of the chip is set as the light emitting direction, a large current can flow while suppressing the current density. Is possible. However, a large chip size means that the number of chips that can be manufactured from one substrate is reduced, resulting in an increase in manufacturing cost. Furthermore, such an LED cannot be applied to a use such as a mobile phone that requires a small chip size.

  Therefore, the present inventors studied an LED having an element structure as described in Patent Document 1 and vertically stacked two light emitting layers having the same emission peak wavelength. Here, in the element structure of Patent Document 1, in the case of the first element structure (pn junction type), the tunnel junction requires a high carrier-doped pn junction, but the high doping for obtaining this tunnel junction is required. In addition to difficulty, the reliability of the light emitting element may be reduced due to diffusion of the dopant. Therefore, the present inventors examined an LED having a second element structure (pn-np structure).

  However, according to the study by the present inventors, in the LED having the element structure, although a slight improvement in the maximum current value and a decrease in the forward voltage were observed as compared with an LED having a light emitting layer, the light emission output It has been found that the improvement in characteristics as expected by obtaining two light emitting layers cannot be obtained.

  Therefore, in view of the above problems, the present invention is a semiconductor light emitting device having two light emitting layers having the same emission peak wavelength, and a semiconductor capable of obtaining a high maximum current value and a light emission output with a low forward voltage. An object of the present invention is to provide a light emitting element and a method for manufacturing the same.

  The present invention relates to a semiconductor light-emitting device having two light-emitting layers having the same emission peak wavelength, and is provided with two light-emitting layers that emit light having different wavelengths as in Patent Document 2. It has nothing to do with things.

  As a result of further studies by the inventors to achieve this object, the following findings were obtained. In the case of an LED having a pn-np structure, current flows from the reference electrode to the back electrode via the first light emitting layer and to the front electrode via the second light emitting layer. Therefore, the first light emitting layer and the second light emitting layer are used. Is driven by a parallel circuit, not a series circuit. When the first and second light emitting layers are driven in a series circuit as in a pn junction type LED, each of the resistance components in the first light emitting layer and the resistance components in the second light emitting layer is different. The current density flowing in the light emitting layer is the same. However, in the case of a parallel circuit, the current density is distributed according to the resistance component of the circuit on the first light emitting layer side and the resistance component of the circuit on the second light emitting layer side. The inventors pay attention to each resistance component, and when the resistance components of the two parallel circuits are different, the current flows preferentially to the circuit side having a low resistance value. The idea is that the output is saturated and the output value of the whole chip does not improve as expected.

  Therefore, the present inventors have drastically improved the characteristics of the light emitting element by devising the element structure so that the resistance components of the current circuit including the first light emitting layer and the current circuit including the second light emitting layer are closer to each other. As a result, the present invention has been completed. That is, elements (composition, area, thickness, arrangement, current path, etc.) caused by the resistance of the current circuit including the first light emitting layer and the current circuit including the second light emitting layer are brought close to each other and ideally equalized. Thus, it has been found that the current bias can be reduced and the characteristics can be dramatically improved.

This invention is made | formed based on the said knowledge, The summary structure is as follows.
(1) On the upper surface side of the support substrate, the intermediate electrode, the lower first conductive type semiconductor layer, the first light emitting layer, the second conductive type semiconductor layer, and the second light emitting layer having the same emission wavelength as the first light emitting layer. , Sequentially comprising an upper first conductive type semiconductor layer and an upper electrode,
A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
A part of an effective region through which the current of the first light emitting layer flows is regulated ;
The semiconductor light emitting device characterized and this is equal to the area of the upper electrode and the intermediate electrode.

  (2) The semiconductor light emitting device according to (1), wherein effective areas of the first light emitting layer and the second light emitting layer are equal.

(3) On the upper surface side of the support substrate, the intermediate electrode, the lower first conductive type semiconductor layer, the first light emitting layer, the second conductive type semiconductor layer, and the second light emitting layer having the same emission wavelength as the first light emitting layer. , Sequentially comprising an upper first conductive type semiconductor layer and an upper electrode,
A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
A portion of the intermediate electrode is regulated ;
The semiconductor light emitting device characterized and this is equal to the area of the upper electrode and the intermediate electrode.

( 4 ) When the intermediate electrode and the upper electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the projection positions of the intermediate electrode and the upper electrode are at least partially overlapped with each other (3) The semiconductor light emitting element as described.

( 5 ) When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode, and the reference electrode and the upper electrode The semiconductor light-emitting device according to (3) or (4), wherein the distances are equal.

( 6 ) On the upper surface side of the support substrate, the intermediate electrode, the lower first conductive type semiconductor layer, the first light emitting layer, the second conductive type semiconductor layer, and the second light emitting layer having the same emission wavelength as the first light emitting layer. , Sequentially comprising an upper first conductive type semiconductor layer and an upper electrode,
A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
A part of an effective region through which the current of the first light emitting layer flows is regulated;
A portion of the intermediate electrode is regulated;
When projecting the intermediate electrode and the upper electrode onto a virtual plane parallel to the upper surface of the support substrate, the projection positions of the intermediate electrode and the upper electrode at least partially overlap ,
A semiconductor light-emitting element, wherein the upper electrode and the intermediate electrode have the same area .

(7) The thickness of the first light-emitting layer and the second light emitting layer are equal, the thickness is equal above the lower first conductive type semiconductor layer and the upper first conductivity type semiconductor layer (1) to (6 The semiconductor light-emitting device according to any one of 1).

( 8 ) The semiconductor light-emitting device according to any one of (1) to ( 7 ), wherein the lower first conductive semiconductor layer and the upper first conductive semiconductor layer have the same composition.

( 9 ) A contact layer is provided in the middle of the second conductivity type semiconductor layer, the second conductivity type semiconductor layer is divided into an upper layer and a lower layer of the contact layer, and the reference electrode is formed on the contact layer. The semiconductor light emitting device according to any one of (1) to ( 8 ), which is disposed.

( 10 ) The semiconductor light emitting element according to ( 9 ), wherein the upper layer and the lower layer have the same thickness.

( 11 ) The semiconductor light-emitting element according to any one of (1) to ( 10 ), further including a lower electrode that mediates electrical connection with the outside of the intermediate electrode.

( 12 ) The semiconductor light-emitting element according to any one of (1) to ( 11 ), wherein the intermediate electrode and the upper electrode are both electrically connected to the support substrate.

( 13 ) On the temporary substrate, the upper first conductive type semiconductor layer, the second light emitting layer, the second conductive type semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive type. Forming a type semiconductor layer sequentially;
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Restricting a part of the effective region through which the current of the first light emitting layer flows ;
A method of manufacturing a semiconductor light emitting device, wherein the upper electrode and the intermediate electrode have the same area .

( 14 ) On the temporary substrate, the upper first conductive type semiconductor layer, the second light emitting layer, the second conductive type semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive type. Forming a type semiconductor layer sequentially;
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Regulating a portion of the intermediate electrode ;
A method of manufacturing a semiconductor light emitting device, wherein the upper electrode and the intermediate electrode have the same area .

(15) when said intermediate electrode and the upper electrode is projected onto the upper surface and parallel to the virtual plane of the supporting substrate, according to the above (14) to overlap at least a portion of the projection position of the intermediate electrode and the upper electrode A method for manufacturing a semiconductor light emitting device.

( 16 ) When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode, the reference electrode, and the upper electrode The method for producing a semiconductor light-emitting element according to ( 14 ), wherein the distances are made equal.

( 17 ) On the temporary substrate, the upper first conductive type semiconductor layer, the second light emitting layer, the second conductive type semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive type. Forming a type semiconductor layer sequentially;
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Restricting a part of the effective region through which the current of the first light emitting layer flows;
Regulating a portion of the intermediate electrode;
When projecting the intermediate electrode and the upper electrode on a virtual plane parallel to the upper surface of the support substrate, at least partially overlap the projection position of the intermediate electrode and the upper electrode ,
The method of manufacturing a semiconductor light emitting element characterized equal to Rukoto the area of said upper electrode and said intermediate electrode.
(18) On the upper surface side of the support substrate, the intermediate electrode, the lower first conductive type semiconductor layer, the first light emitting layer, the second conductive type semiconductor layer, and the second light emitting layer having the same emission wavelength as the first light emitting layer. , Sequentially comprising an upper first conductive type semiconductor layer and an upper electrode,
A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
A portion of the intermediate electrode is regulated;
When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are as follows: A semiconductor light emitting element characterized by being equal.
(19) On the upper surface side of the support substrate, the intermediate electrode, the lower first conductive semiconductor layer, the first light emitting layer, the second conductive semiconductor layer, and the second light emitting layer having the same emission wavelength as the first light emitting layer. , Sequentially comprising an upper first conductive type semiconductor layer and an upper electrode,
A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
A part of an effective region through which the current of the first light emitting layer flows is regulated;
A portion of the intermediate electrode is regulated;
When projecting the intermediate electrode and the upper electrode onto a virtual plane parallel to the upper surface of the support substrate, the projection positions of the intermediate electrode and the upper electrode at least partially overlap,
When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are as follows: A semiconductor light emitting element characterized by being equal.
(20) The semiconductor light emitting element according to the above (18) or (19), wherein effective areas of the first light emitting layer and the second light emitting layer are equal.
(21) On the temporary substrate, the upper first conductive semiconductor layer, the second light emitting layer, the second conductive semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive Forming a type semiconductor layer sequentially;
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Restricting a part of the effective region through which the current of the first light emitting layer flows;
When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are determined. A method of manufacturing a semiconductor light emitting device, characterized in that they are equal.
(22) On the temporary substrate, the upper first conductive type semiconductor layer, the second light emitting layer, the second conductive type semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive type. Forming a type semiconductor layer sequentially;
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Regulating a portion of the intermediate electrode;
When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are determined. A method of manufacturing a semiconductor light emitting device, characterized in that they are equal.
(23) On the temporary substrate, the upper first conductive type semiconductor layer, the second light emitting layer, the second conductive type semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive type. Forming a type semiconductor layer sequentially;
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Restricting a part of the effective region through which the current of the first light emitting layer flows;
Regulating a portion of the intermediate electrode;
When projecting the intermediate electrode and the upper electrode on a virtual plane parallel to the upper surface of the support substrate, at least partially overlap the projection position of the intermediate electrode and the upper electrode,
When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are determined. A method of manufacturing a semiconductor light emitting device, characterized in that they are equal.
(24) The method for manufacturing a semiconductor light-emitting element according to any one of (21) to (23), wherein effective areas of the first light-emitting layer and the second light-emitting layer are equalized.

  According to the present invention, in a semiconductor light emitting device having two light emitting layers having the same emission peak wavelength, the resistance components of the current circuit including the first light emitting layer and the current circuit including the second light emitting layer are made closer to each other. Further, by devising the element structure, it is possible to obtain a high maximum current value and light emission output with a low forward voltage.

1A is a schematic sectional view and FIG. 1B is a schematic top view of a semiconductor light emitting device 100 according to the present invention. It is (A) schematic cross section and (B) vertical top view of another semiconductor light emitting element 200 according to the present invention. It is (A) schematic cross section and (B) vertical top view of another semiconductor light emitting element 300 according to the present invention. It is (A) schematic cross section and (B) vertical top view of another semiconductor light emitting element 400 according to the present invention. It is (A) schematic cross section and (B) vertical top view of another semiconductor light emitting element 500 according to the present invention. It is (A) schematic cross section and (B) vertical top view of another semiconductor light emitting element 600 according to the present invention. 5A is a schematic sectional view and FIG. 5B is a schematic top view of a semiconductor light emitting device 700 of Comparative Example 1. FIG. It is a figure which shows the relationship of the light emission output with respect to the electric current applied to the semiconductor light-emitting element of an Example and a comparative example.

  Hereinafter, the present invention will be described in more detail with reference to the drawings. In the present specification, components that are common to the semiconductor light emitting device according to the present invention and the semiconductor light emitting device of the comparative example are denoted by the same reference numerals in the last two digits in principle, and description thereof is omitted. In the schematic cross-sectional view of the light-emitting element, for convenience of explanation, the thickness of each layer is exaggerated at a ratio different from the actual state.

(Embodiment 1: Semiconductor light emitting device 100)
As shown in FIG. 1A, a semiconductor light emitting device 100 according to an embodiment of the present invention includes an intermediate electrode (light emitting layer side contact metal layer) 104, a lower first conductive semiconductor on the upper surface side of a support substrate 102. An n-type semiconductor layer 106 as a layer, a first light-emitting layer 108, a p-type semiconductor layer 110 as a second conductive semiconductor layer, a second light-emitting layer 112 having the same light emission wavelength as the first light-emitting layer 108, an upper first An n-type semiconductor layer 114 and an upper electrode 116 as a conductive semiconductor layer are sequentially provided, and pass through the lower electrode 118 provided on the lower surface side of the support substrate 102, the upper first conductive semiconductor layer 114 and the second light emitting layer 112. And a reference electrode 122 that is provided in the recessed portion 120 that is electrically connected to the second conductivity type semiconductor layer 110. The element 100 is a wafer-bonded element formed by bonding a temporary substrate on which an epitaxial film including first and second light emitting layers 108 and 112 is grown and a support substrate 102, and is formed by supporting substrate-side contact metal. The support substrate side bonding metal layer 132 formed through the layer 130 and the light emitting layer side bonding metal layer 128 are bonded, and the temporary substrate is removed or separated after bonding.

  As an example of mounting the element 100, the reference electrode 122 is connected to the positive electrode (+) terminal, and the upper electrode 116 and the lower electrode 118 are connected to the negative electrode (−) terminal. Then, a first circuit in which a current flows from the reference electrode 122 through the first light emitting layer 108 to the intermediate electrode 104, the support substrate 102, and the lower electrode 118, and an upper side from the reference electrode 122 through the second light emitting layer 112. Two parallel circuits are formed with the second circuit through which current flows to the electrode 116.

  Here, in the element 100, as shown in FIGS. 1A and 1B, since the second light emitting layer 112 is partially removed by the circular recess 120, the second light emitting layer 112 is removed. The area is smaller than that of the first light emitting layer 108 by the amount. In the element 100, a part of the first light emitting layer 108 is divided by a circular protrusion formed of the insulating film 126 by the area of the second light emitting layer 112 removed by the recess 120. That is, a part of the effective region where the current of the first light emitting layer 108 flows is regulated so as to compensate for the area difference between the effective regions of the first light emitting layer 108 and the second light emitting layer 112 caused by the presence of the recess 120. Yes. As a result, no current flows through the portion of the first light emitting layer 108 delimited by the protrusions. By adopting this configuration, the resistance component in each light emitting layer in the first and second circuits can be made closer. Therefore, current flows uniformly through the first light emitting layer 108 and the second light emitting layer 112, and the characteristics of the light emitting element 100 can be dramatically improved.

  A broken line in FIG. 1B indicates a removed portion of the second light emitting layer 112 by the recess 120 and an isolated portion of the first light emitting layer 108 by the insulating film 126. In the present embodiment, as described above, the areas of the portions where the current flows in the first light emitting layer 108 and the second light emitting layer 112 are equal. In this specification, the area of the portion where current can flow in the light emitting layer is referred to as “effective area”. The element 100 of the present embodiment is characterized in that the effective areas of the first light emitting layer 108 and the second light emitting layer 112 are made equal. Therefore, the resistance component in each light emitting layer in the first and second circuits can be made closer, so that the characteristics of the light emitting element 100 can be dramatically improved.

  Here, in FIG. 1, the first light emitting layer 108b and the lower first conductive semiconductor layer 106 are left on the inner side separated by the insulating film 126, but an insulating portion or other materials may be used. . That is, the present invention is not particularly limited as long as the effective region in which the current of the first light emitting layer 108 flows is regulated to produce the above-described effects. However, for example, when problems such as a difference in thermal expansion coefficient or cracks due to the formation of the reference electrode occur, it is preferable that the insulating portion, which is a different material for the light emitting element, be formed in a necessary and sufficient shape, and be located on the inner side separated by the insulating film. It is more preferable to leave the first light emitting layer 108 and the lower first conductive semiconductor layer 106.

  The first light emitting layer 108 and the second light emitting layer 112 are preferably equal in thickness. Thereby, the resistance component in each light emitting layer in a 1st and 2nd circuit can be made equal, and the resistance component in a 1st and 2nd circuit can be brought closer.

  Making the thickness and / or composition of the n-type semiconductor layer 106 that is the lower first conductive semiconductor layer 106 and the n-type semiconductor layer 114 that is the upper first conductive semiconductor layer equal in the first and second circuits The resistance component can be made closer, which is preferable.

  In addition, the element 100 includes a contact layer 124 in the middle of the p-type semiconductor layer 110 that is the second conductivity type semiconductor layer, and the p-type semiconductor layer 110 is divided into an upper layer 110a and a lower layer 110b on the basis of the contact layer 124. The reference electrode 122 is divided and disposed on the contact layer 124. At this time, it is preferable to make the resistance components in the first and second circuits closer by making the thicknesses of the upper layer 110a and the lower layer 110b equal.

  Here, the expression “equal” such as “equal effective area” and “equal thickness” in this specification does not mean that the effective area, thickness, etc. are equal in a strictly mathematical sense. Of course, it includes errors that are unavoidable in the manufacturing process and includes errors that are allowed within the scope of the effects of the present invention, and this is also the case in other embodiments. As such an error, 3% or less is included in “equal”.

  As a suitable material constituting each layer of the semiconductor layer, a compound semiconductor is exemplified, and for example, a group III-V compound semiconductor can be used. As the group III-V compound semiconductor, for example, the n-type semiconductor layers 106 and 114 and the p-type semiconductor layer 110 can be made of an AlGaAs material, an AlGaInP material, an AlGaN material, or the like. Examples of the p-type impurity include Mg, Zn, and C, and examples of the n-type impurity include Si, Te, and Se. The light emitting layers 108 and 112 can be a single layer made of an AlGaAs-based material, an AlGaAsInP-based material, an AlGaN-based material, or a laminated structure such as a multiple quantum well. Any of these can be formed by epitaxial growth using a known method such as MOCVD. The emission wavelength is not particularly limited because it depends on the material configuration of the light emitting layer, and can be, for example, in the range of 250 to 950 nm. Here, the first and second light-emitting layers are light-emitting layers having the same composition, and “having the same light emission wavelength” in this specification means that the light emission peak wavelengths are the same. However, it should be understood that it includes errors unavoidable in the crystal growth process, such as in-plane distribution, and errors that are allowed within the range where the effects of the present invention are exerted, and the emission peak wavelength in the first circuit and the second circuit. An error within 20 nm is allowed with respect to the emission peak wavelength. The thickness of each layer can be, for example, 1 to 10 μm for the n-type semiconductor layers 106 and 114, 10 to 500 nm (total thickness) for the light emitting layers 108 and 112, and 1 to 10 μm for the p-type semiconductor layer 110. Although the semiconductor layer has been described so far with the first conductivity type in the present invention being n-type and the second conductivity type being p-type, the present invention is not limited to this including other embodiments, and the first conductivity type is Of course, the p-type and the second conductivity type may be n-type.

  The p-type contact layer 124 is a second conductivity type semiconductor layer having a composition different from that of the second conductivity type semiconductor layer 110, and is preferably located at the center in the thickness direction of the second conductivity type semiconductor layer 110. By changing the composition, the timing of stopping the etching when forming the recess 120 can be matched with the surface of the contact layer, and by setting the position to the center in the thickness direction of the second conductivity type semiconductor layer 110, The thickness of the second conductive semiconductor layer 110 from the reference electrode 122 can be made equal in the upward direction and the downward direction. The composition of the contact layer 124 is not particularly limited as long as the timing of stopping the etching is known, such as the etching rate is slower than others depending on the conditions of wet etching and dry etching. For example, in the case of an AlGaAs infrared LED in the 850 nm band, the Al composition of the p-type contact layer 124 is desirably 0.4 or more, but the etchant composition is optimal even if the Al composition is less than 0.4. It is possible to stop the etching by making it. However, in order to carry out with the ammonia hydrogen peroxide mixed solution, the Al composition needs the relationship of the semiconductor layer 110 <p-type contact layer 124. As described above, in the AlGaAs system, the etching of the composition in a specific Al content range can be stopped by the ammonia hydrogen peroxide solution etching solution composition. Note that the contact layer 124 may be designed so that the resistance between the contact layer 124 and the reference electrode 122 is small, and the type and doping amount of the dopant may be changed with respect to the second conductivity type semiconductor layer 110.

  Suitable materials for forming the support substrate 102 include, for example, semiconductor materials such as Si, GaAs, and Ge, metals such as Al and Cu, or alloy materials thereof, and preferably have a thickness of 100 to 400 μm. Have.

  The upper electrode 116 is, for example, an ohmic contact layer (50 to 1000 nm) made of an AuGe-based alloy material, and a wire bonding pad layer (Ti: 50) made of a Ti / Au electrode in which Au is formed on Ti as an adhesion layer. ˜200 nm, Au: 1 to 3 μm). As the Au-based alloy material, AuGe / Ni / Au can be used in the case of an electrode in contact with the AlGaAs-based material.

  The reference electrode 122 is, for example, an ohmic contact layer (50 to 1000 nm) made of an Au-based alloy material, and a wire bonding pad layer (for example, Ti: Ti) made of a Ti / Au electrode in which Au is formed on Ti as an adhesion layer. 50 to 200 nm, Au: 1 to 3 μm). As the Au-based alloy material, for example, AuZn can be used in the case of an electrode in contact with an AlGaAs-based material.

  When the support substrate 102 is a semiconductor material, the lower electrode 118 is selected from materials that form an ohmic junction with the semiconductor material. For example, when n-type GaAs is selected as the support substrate, an AuGe / Ni / Au stacked layer is selected. Etc. can be selected. The same applies to the support substrate side contact metal layer 130.

  In this embodiment, the lower electrode 118 plays a role of mediating electrical connection with the outside of the intermediate electrode. When the support substrate 102 is not used as a current path, the lower electrode 118 is formed on the support substrate. It may be formed and directly connected to the intermediate electrode. Further, when a metal substrate, metal plating, or the like is used as the support substrate 102, the support substrate 102 itself can be configured to also serve as the lower electrode 118, and the support substrate 102 is regarded as the lower electrode 118. You can also. In the present invention, since the current flowing through the first circuit including the first light emitting layer 108 may be extracted from the intermediate electrode 104, the lower electrode 118 is not an essential component.

  The intermediate electrode 104 is an electrode for forming good ohmic contact with the lower first conductive semiconductor layer 106 (n-type semiconductor layer in the present embodiment). A suitable material constituting the intermediate electrode 104 is, for example, an AuGe / Ni / Au electrode in which AuGe, Ni and Au are sequentially formed, and preferably has a thickness of 100 to 1000 nm.

  Examples of the support substrate side bonding metal layer 132 and the light emitting layer side bonding metal layer 128 include a Ti / Au laminate (Au thickness: several μm).

Examples of the insulating film 126 include SiN, SiO ₂ , and AlN. The insulating film 126 preferably has a thickness of 100 to 1000 nm, and has the same thickness as that of the intermediate electrode 104 except for the protruding portion.

  The method for measuring the film thickness on the wafer in this specification is based on a stylus-type step gauge, and the five points on the wafer surface (on the diagonal line passing through the wafer center in the case of the 3-inch substrate of this embodiment) Thus, the average value of the measurement of 5 points at an equal distance with two points 1 cm inside from the outer periphery of the wafer as both ends is obtained.

  Next, an example of a method for manufacturing the semiconductor light emitting device 100 will be described. First, the support substrate side contact metal layer 130 and the support substrate side bonding metal layer 132 are formed on the support substrate 102 such as an n-type GaAs substrate by, for example, sputtering, electron beam evaporation, or resistance heating evaporation (S1). . At this time, the support substrate side contact metal layer 130 is alloyed by performing a predetermined heat treatment. In this specification, the “resistance heating vapor deposition method” is a method of vapor deposition by heating and evaporating a metal in a vacuum, and in order to heat the vapor deposition metal, a base of a high melting point material on which the vapor deposition metal is placed. It is a method of energizing (for example, a tungsten wire or a boat) to increase the temperature by heat generated by metal resistance.

  Next, an n-type semiconductor layer 114, a second light emitting layer 112, a p-type semiconductor layer (upper layer) 110a, a contact layer 124, a p-type semiconductor layer (lower side) on a temporary substrate (not shown) such as an n-type GaAs substrate. Layer) 110b, the first light emitting layer 108, and the n-type semiconductor layer 106 are sequentially epitaxially grown by, eg, MOCVD (S2).

Then, in order to form an insulating film 126 for isolating a part of the first light emitting layer 108, a circular or donut-shaped groove reaching the first light emitting layer 108 is formed on the n-type semiconductor layer 106 (S3). . In this step, a predetermined pattern is formed with a photoresist, and then a groove is formed by etching. After removing the resist, an insulating film is formed by plasma CVD or sputtering, and a circular pattern with the groove as the outer periphery is formed by photoresist. Then, the insulating film other than the circular portion is removed by etching, and the first light emission An insulating film 126 including a protrusion reaching the layer 108 is formed (S4). The shape of the groove and the insulating portion is not limited to the above as long as a closed region where no current flows is formed in the first light emitting layer 108. For the insulating film, an insulating material generally used for a semiconductor light emitting element may be used, and examples thereof include SiN, SiO ₂ , and AlN.

  Next, the intermediate electrode 104 and the light emitting layer side bonding metal layer 128 are formed on the n-type semiconductor layer 106 by, for example, sputtering, electron beam evaporation, or resistance heating evaporation (S5). Note that the intermediate electrode 104 may be formed in a region other than the insulating film in order to planarize the bonding surface.

  Here, the temporary substrate and the support substrate 102 are joined by thermocompression bonding the light emitting layer side joining metal layer 128 and the support substrate side joining metal layer 132 at a temperature in the range of 250 to 400 ° C. for 15 to 120 minutes, for example. (S6). Thereafter, the temporary substrate can be removed and separated by, for example, polishing or wet etching (S7). The etching solution can be appropriately selected depending on the material of the temporary substrate or the separation location.

  Next, an electrode metal is formed on the n-type semiconductor layer 114 by, for example, sputtering, electron beam evaporation, or resistance heating evaporation, a resist pattern is formed by photolithography, and etching is performed to remove the resist. Then, the upper electrode 116 having a predetermined shape is formed (S8). Further, after forming a protective pattern other than the portion that becomes the recess 120 by using a photoresist, the recess 120 is formed by etching (S9). At this time, the p-type contact layer 124 functions as an etching stop layer. Next, the reference electrode 122 is formed (S10). Specifically, a pattern that protects the portions other than the electrode formation portion is formed with a photoresist, and after depositing an electrode metal by, for example, sputtering, electron beam evaporation, or resistance heating evaporation, the metal on the resist is resisted by lift-off. Then, the reference electrode 122 is formed.

  Here, in the recess 120, it is preferable that at least a part of the outer periphery of the groove formed for forming the insulating film 126 overlaps with the projection position viewed from the upper surface of the element, and it is more preferable that the center position and the shape are the same. Furthermore, the cross-sectional shape of the recess 120 is preferably symmetric with respect to the contact layer 124 and the cross-sectional shape of the outer periphery of the groove formed for forming the insulating film 126. This is to make the effective area of the second light emitting layer 112 equal to the effective area of the first light emitting layer 108. Further, the effective regions of the first light emitting layer 108 and the second light emitting layer 112 are aligned so as to be equidistant from the reference electrode 122. Further, since it is difficult to extract light from the reference electrode 122, there is a secondary effect of increasing the current consumption efficiency by not causing the first light emitting layer 108 below to emit light.

  Next, an electrode metal is formed on the back surface of the support substrate (the surface on which the light emitting layer is not formed) by, for example, sputtering, electron beam evaporation, or resistance heating evaporation, and a predetermined heat treatment is performed to form an alloy. To form the lower electrode 118 (S11). Finally, dicing is performed (S12), and an LED element using the semiconductor light emitting element 100 can be manufactured.

(Embodiment 2: Semiconductor light emitting device 200)
A semiconductor light emitting device 200 according to another embodiment of the present invention includes an intermediate electrode (light emitting layer side contact metal layer) 204, a lower first conductivity type on the upper surface side of a support substrate 202, as shown in FIG. An n-type semiconductor layer 206 as a semiconductor layer, a first light-emitting layer 208, a p-type semiconductor layer 210 as a second conductive semiconductor layer, a second light-emitting layer 212 having the same emission wavelength as the first light-emitting layer 208, an upper first The n-type semiconductor layer 214 and the upper electrode 216 as one conductivity type semiconductor layer are sequentially provided, and the lower electrode 218 provided on the lower surface side of the support substrate 202, the upper first conductivity type semiconductor layer 214, and the second light emitting layer 212 are provided. The reference electrode 222 is provided in the recessed portion 220 that penetrates and is electrically connected to the second conductivity type semiconductor layer 210. The element 200 is a wafer-bonded element formed by bonding a temporary substrate on which an epitaxial film including first and second light emitting layers 208 and 212 is grown and a support substrate 202, and is provided on a support substrate side contact metal. The support substrate side bonding metal layer 232 formed via the layer 230 and the light emitting layer side bonding metal layer 228 are bonded, and the temporary substrate is removed or separated after bonding.

  As an example of mounting the element 200, the reference electrode 222 is connected to the positive electrode (+) terminal, and the upper electrode 216 and the lower electrode 218 are connected to the negative electrode (−) terminal. Then, a first circuit in which current flows from the reference electrode 222 to the intermediate electrode 204, the support substrate 202, and further to the lower electrode 218 through the first light emitting layer 208, and an upper side from the reference electrode 222 through the second light emitting layer 212. Two parallel circuits are formed with the second circuit through which current flows to electrode 216.

  Here, in the element 200, as shown in FIG. 2B, the intermediate electrode 204 has a circular shape with a diameter r (n2), and an insulating film 226 surrounds the intermediate electrode 204. R (n2) is equal to the diameter r (n1) of the upper electrode 216. Therefore, the area where the upper electrode 216 contacts the n-type semiconductor layer 214 and the area where the intermediate electrode 204 contacts the n-type semiconductor layer 206 are equal. The area of the portion where each electrode is in contact with the adjacent semiconductor layer is referred to as “electrode area” in this specification. The element 200 of this embodiment is characterized in that the areas of the upper electrode 216 and the intermediate electrode 204 are equal. By adopting this configuration, the resistance component at each electrode portion in the first and second circuits can be made closer. Therefore, current flows uniformly through the first light emitting layer 208 and the second light emitting layer 212, and the characteristics of the light emitting element 200 can be dramatically improved.

  As shown in FIG. 2A, the upper electrode 216 formed on the n-type semiconductor layer 214 cannot be formed on the n-type semiconductor layer 214 portion removed by the recess 220. For this reason, when the intermediate electrode 204 is formed on the entire surface of the n-type semiconductor layer 206, an area difference occurs between the upper electrode 216 and the intermediate electrode 204. Therefore, in the present embodiment, by restricting a part of the intermediate electrode 204 by the insulating film 226, the difference in area is compensated, and the resistance component at each electrode part in the first and second circuits is made closer.

  Further, in the element 200, as shown in FIG. 2B, when the intermediate electrode 204, the upper electrode 216, and the reference electrode 222 are projected on a virtual plane parallel to the upper surface of the support substrate 202, the reference electrode 222, the intermediate electrode 204, And the distance L1 between the reference electrode 222 and the upper electrode 216 are equal. Here, the distances L1 and L2 mean the distance between the centers of the electrodes in the case of circular electrodes as in the present embodiment. Therefore, the resistance component in the current path from the reference electrode 222 to the intermediate electrode 204 and the upper electrode 216 in the first and second circuits can be made closer, and the resistance component in the first and second circuits can be made closer. Is preferable.

  The first light emitting layer 208 and the second light emitting layer 212 are preferably equal in thickness. Thereby, the resistance component in each light emitting layer in a 1st and 2nd circuit can be made equal, and the resistance component in a 1st and 2nd circuit can be brought closer.

  Making the thickness and / or composition of the n-type semiconductor layer 206 as the lower first conductive semiconductor layer 206 and the n-type semiconductor layer 214 as the upper first conductive semiconductor layer equal in the first and second circuits The resistance component can be made closer, which is preferable.

  Further, the element 200 includes a contact layer 224 in the middle of the p-type semiconductor layer 210 that is the second conductivity type semiconductor layer, and the p-type semiconductor layer 210 is divided into an upper layer 210a and a lower layer 210b on the basis of the contact layer 224. The reference electrode 222 is divided and disposed on the contact layer 224. At this time, it is preferable to make the resistance components in the first and second circuits closer by making the thicknesses of the upper layer 210a and the lower layer 210b equal.

  A suitable material, thickness, and the like of each component of the element 200 are the same as those in the first embodiment.

  In addition, an example of a method for manufacturing the element 200 will be described below by extracting only parts different from the first embodiment. In the manufacturing process of the element 200, the step S3 in the first embodiment is not performed. In step S4, an insulating film is formed on the n-type semiconductor layer 206 by a plasma CVD method or a sputtering method, and a pattern having a circular concave portion with a diameter r (n2) is formed with a photoresist. The insulating film in the circular portion is removed, and an insulating film 226 is formed. Other steps are the same as those in the first embodiment.

(Embodiment 3: Semiconductor light emitting device 300)
As shown in FIG. 3A, a semiconductor light emitting device 300 according to another embodiment of the present invention has an intermediate electrode (light emitting layer side contact metal layer) 304, a lower first conductivity type on the upper surface side of a support substrate 302. The n-type semiconductor layer 306 as the semiconductor layer, the first light-emitting layer 308, the p-type semiconductor layer 310 as the second conductive semiconductor layer, the second light-emitting layer 312 having the same light emission wavelength as the first light-emitting layer 308, the upper first An n-type semiconductor layer 314 and an upper electrode 316 are sequentially provided as one conductivity type semiconductor layer, and a lower electrode 318 provided on the lower surface side of the support substrate 302, an upper first conductivity type semiconductor layer 314, and a second light emitting layer 312 are provided. A reference electrode 322 is provided in the penetrating recess 320 and electrically connected to the second conductivity type semiconductor layer 310. This element 300 is a wafer-bonded element formed by bonding a temporary substrate on which an epitaxial film including first and second light emitting layers 308 and 312 is grown and a support substrate 302, and is a support substrate side contact metal. The support substrate side bonding metal layer 332 formed through the layer 330 and the light emitting layer side bonding metal layer 328 are bonded, and the temporary substrate is removed or separated after bonding.

  As an example of mounting the element 300, the reference electrode 322 is connected to the positive electrode (+) terminal, and the upper electrode 316 and the lower electrode 318 are connected to the negative electrode (−) terminal. Then, a first circuit in which current flows from the reference electrode 322 through the first light emitting layer 308 to the intermediate electrode 304, the support substrate 302, and the lower electrode 318, and an upper side from the reference electrode 322 through the second light emitting layer 312. Two parallel circuits are formed with the second circuit through which current flows to electrode 316.

  Here, in the element 300, as shown in FIG. 3B, the upper electrode 316 and the intermediate electrode 304 overlap with each other when viewed from the upper surface of the element, and the electrode centers coincide. Therefore, when the intermediate electrode 304, the upper electrode 316, and the reference electrode 322 are projected on a virtual plane parallel to the upper surface of the support substrate 202, the distance between the reference electrode 322 and the intermediate electrode 304 and the relationship between the reference electrode 322 and the upper electrode 316. The distance is equal. Here, the distance between the electrodes means the distance between the centers of the electrodes when the electrodes are circular as in the present embodiment, and the distance between the centers of the circumscribed circles of the electrodes when the electrodes are not circular. In the element 300 of this embodiment, when the intermediate electrode 304 and the upper electrode 316 are projected onto a virtual plane parallel to the upper surface of the support substrate 202, the projection positions of the upper electrode 316 and the intermediate electrode 304 at least partially overlap. Therefore, the resistance component in the current path from the reference electrode 322 to the intermediate electrode 304 and the upper electrode 316 in the first and second circuits can be made closer. Therefore, current flows uniformly through the first light-emitting layer 308 and the second light-emitting layer 312 and the characteristics of the light-emitting element 300 can be dramatically improved. From the viewpoint of bringing the resistance components of the first and second circuits closer, it is more preferable that the projection positions in the element vertical direction of the intermediate electrode 304 and the upper electrode 316 are equal as in the present embodiment. Here, “the projection positions are equal” means that the centers of the circumscribed circles of the two electrodes coincide when the electrodes are circular or rectangular.

  The first light emitting layer 308 and the second light emitting layer 312 are preferably equal in thickness. Thereby, the resistance component in each light emitting layer in a 1st and 2nd circuit can be made equal, and the resistance component in a 1st and 2nd circuit can be brought closer.

  Making the thickness and / or composition of the n-type semiconductor layer 306 as the lower first conductive semiconductor layer 306 and the n-type semiconductor layer 314 as the upper first conductive semiconductor layer equal in the first and second circuits The resistance component can be made closer, which is preferable.

  In addition, the element 300 includes a contact layer 324 in the middle of the p-type semiconductor layer 310 that is the second conductivity type semiconductor layer, and the p-type semiconductor layer 310 is divided into an upper layer 310a and a lower layer 310b with reference to the contact layer 324. The reference electrode 322 is divided and disposed on the contact layer 324. At this time, it is preferable to make the resistance components in the first and second circuits closer by making the thicknesses of the upper layer 310a and the lower layer 310b equal.

  A suitable material, thickness, and the like of each component of the element 300 are the same as those in the first embodiment. An example of a method for manufacturing the element 300 is the same as that in the second embodiment except that the pattern shape in the intermediate process is changed as appropriate, and thus the description thereof is omitted.

(Embodiment 4: Semiconductor light emitting device 400)
As shown in FIG. 4A, a semiconductor light emitting device 400 according to another embodiment of the present invention includes an intermediate electrode (light emitting layer side contact metal layer) 404, a lower first conductivity type on the upper surface side of a support substrate 402. The n-type semiconductor layer 406 as the semiconductor layer, the first light-emitting layer 408, the p-type semiconductor layer 410 as the second conductive semiconductor layer, the second light-emitting layer 412 having the same light emission wavelength as the first light-emitting layer 408, the upper first An n-type semiconductor layer 414 and an upper electrode 416 as one conductivity type semiconductor layer are sequentially provided, and a lower electrode 418 provided on the lower surface side of the support substrate 402, an upper first conductivity type semiconductor layer 414, and a second light emitting layer 412 are provided. A reference electrode 422 is provided in the penetrating recess 420 and electrically connected to the second conductivity type semiconductor layer 410. This element 400 is a wafer-bonded element formed by bonding a temporary substrate on which an epitaxial film including first and second light emitting layers 408 and 412 is grown and a support substrate 402, and is a support substrate side contact metal. The support substrate side bonding metal layer 432 formed through the layer 430 and the light emitting layer side bonding metal layer 428 are bonded, and the temporary substrate is removed or separated after bonding.

  As an example of mounting the element 400, the reference electrode 422 is connected to a positive electrode (+) terminal, and the upper electrode 416 and the lower electrode 418 are connected to a negative electrode (−) terminal. Then, the first circuit in which current flows from the reference electrode 422 to the intermediate electrode 404, the support substrate 402, and further the lower electrode 418 through the first light emitting layer 408, and the upper side from the reference electrode 422 through the second light emitting layer 412. Two parallel circuits are formed with the second circuit through which current flows to electrode 416.

  Here, in the element 400, the concave portion 420 and the reference electrode 422 are provided in the central portion of the element, and the upper electrode 416 is arranged in a linear shape so as to surround the reference electrode 422. A pad electrode 417 was formed on part of the upper electrode 416. Further, as shown by a broken line in FIG. 4B, a plurality of the central electrodes 404 are arranged so as to be evenly distributed around the reference electrode as viewed from the top.

  In the element 400, the area of the upper electrode 416 and the area of the intermediate electrode 404 are equal, and the resistance component at each electrode portion in the first and second circuits can be made closer as in the second embodiment. Therefore, current flows evenly through the first light-emitting layer 408 and the second light-emitting layer 412, and the characteristics of the light-emitting element 400 can be dramatically improved. Note that the area of the intermediate electrode 404 is the sum of the areas of the plurality of intermediate electrodes, and only part of the area is shown in FIG. Exists.

  The first light emitting layer 408 and the second light emitting layer 412 are preferably equal in thickness. Thereby, the resistance component in each light emitting layer in a 1st and 2nd circuit can be made equal, and the resistance component in a 1st and 2nd circuit can be brought closer.

  Making the thickness and / or composition of the n-type semiconductor layer 406 that is the lower first conductive semiconductor layer and the n-type semiconductor layer 414 that is the upper first conductive semiconductor layer equal in the first and second circuits The resistance component can be made closer, which is preferable.

  In addition, the element 400 includes a contact layer 424 in the middle of the p-type semiconductor layer 410 that is the second conductivity type semiconductor layer, and the p-type semiconductor layer 410 is divided into an upper layer 410a and a lower layer 410b on the basis of the contact layer 424. The reference electrode 422 is divided and disposed on the contact layer 424. At this time, it is preferable to make the resistance components in the first and second circuits closer by making the thicknesses of the upper layer 410a and the lower layer 410b equal.

  A suitable material, thickness, and the like of each component of the element 400 are the same as those in the first embodiment. An example of a method for manufacturing the element 400 is the same as that of the second embodiment except that the pattern shape in the intermediate process is changed as appropriate, and thus the description thereof is omitted. The upper electrode 416 can be formed as follows. First, a pattern that protects the portion other than the electrode 416 formation portion is formed with a photoresist, and AuGe / Ni / Au (thickness: 800 nm) is formed by a resistance heating method, and immersed in acetone / dimethyl sulfoxide, and the resist is swollen to form a resist. The upper metal is removed together with the resist, and thereafter alloying is performed by heat treatment at 400 to 450 ° C. to form the electrode 416. Next, the pad electrode 417 can be formed as follows. First, a pattern that protects the portion other than the electrode 417 formation portion is formed with a photoresist, and further Ti / Au (thickness: 100 nm / 1 μm) is formed, and immersed in acetone / dimethyl sulfoxide, the resist is swollen, and then on the resist. The metal is removed together with the resist to form an electrode 417.

(Embodiment 5: Semiconductor light emitting element 500)
As shown in FIG. 5A, a semiconductor light emitting device 500 according to another embodiment of the present invention has an intermediate electrode (light emitting layer side contact metal layer) 504 and a lower first conductive type on the upper surface side of a support substrate 502. The n-type semiconductor layer 506 as the semiconductor layer, the first light-emitting layer 508, the p-type semiconductor layer 510 as the second conductive semiconductor layer, the second light-emitting layer 512 having the same light emission wavelength as the first light-emitting layer 508, the upper first The n-type semiconductor layer 514 and the upper electrode 516 as one conductivity type semiconductor layer are sequentially provided. The lower electrode 518 provided on the lower surface side of the support substrate 502, the upper first conductivity type semiconductor layer 514, and the second light emitting layer 512 are provided. A reference electrode 522 provided in the penetrating recess 520 and electrically connected to the second conductivity type semiconductor layer 510 is provided. This element 500 is a wafer bonding type element formed by bonding a temporary substrate on which an epitaxial film including first and second light emitting layers 508 and 512 is grown and a support substrate 502, and is a support substrate side contact metal. The support substrate side bonding metal layer 532 formed through the layer 530 and the light emitting layer side bonding metal layer 528 are bonded, and the temporary substrate is removed or separated after bonding.

  As an example of mounting the element 500, the reference electrode 522 is connected to the positive electrode (+) terminal, and the upper electrode 516 and the lower electrode 518 are connected to the negative electrode (−) terminal. Then, a first circuit in which current flows from the reference electrode 522 to the intermediate electrode 504 through the first light emitting layer 508, the support substrate 502, and the lower electrode 518, and the upper side from the reference electrode 522 through the second light emitting layer 512. Two parallel circuits are formed with the second circuit through which current flows to electrode 516.

  Here, the element 500 has a configuration in which the insulating film 526 having the protrusions of the first embodiment is added to the element 400 of the fourth embodiment.

  That is, the element 500 is provided with a recess 520 and a reference electrode 522 at the center of the element, and the upper electrode 516 is disposed in a rectangular shape so as to surround the reference electrode 522. A pad electrode 517 was formed on a part of the upper electrode 516. Further, as shown by a broken line in FIG. 5B, a plurality of the central electrodes 504 are arranged so as to be evenly distributed around the reference electrode as viewed from above. The area of the upper electrode 516 and the area of the intermediate electrode 504 are equal, and the resistance component at each electrode portion in the first and second circuits can be made closer as in the second embodiment.

  Further, since the first light emitting layer 508 is partly isolated by the insulating film 526 having protrusions, the effective areas of the first light emitting layer 508 and the second light emitting layer 512 are equal. Therefore, the resistance component in each light emitting layer in the first and second circuits can be made closer.

  With such a configuration, the characteristics of the semiconductor light emitting device can be further improved.

  The first light emitting layer 508 and the second light emitting layer 512 are preferably equal in thickness. Thereby, the resistance component in each light emitting layer in a 1st and 2nd circuit can be made equal, and the resistance component in a 1st and 2nd circuit can be brought closer.

  Making the thickness and / or composition of the n-type semiconductor layer 506, which is the lower first conductive semiconductor layer, and the n-type semiconductor layer 514, which is the upper first conductive semiconductor layer, equal in the first and second circuits The resistance component can be made closer, which is preferable.

  The element 500 includes a contact layer 524 in the middle of the p-type semiconductor layer 510 that is the second conductivity type semiconductor layer, and the p-type semiconductor layer 510 is divided into an upper layer 510a and a lower layer 510b on the basis of the contact layer 524. The divided reference electrode 522 is disposed on the contact layer 524. At this time, it is preferable to make the resistance components in the first and second circuits closer by making the thicknesses of the upper layer 510a and the lower layer 510b equal.

  A suitable material, thickness, and the like of each component of the element 500 are the same as those in the first and fourth embodiments. An example of a method for manufacturing the element 500 is omitted from the description of Embodiments 1 and 4 because it is clear from the description of Embodiments 1 and 4.

Embodiment 6 Semiconductor Light Emitting Element 600
As shown in FIG. 6A, a semiconductor light emitting device 600 according to another embodiment of the present invention has an intermediate electrode (light emitting layer side contact metal layer) 604 and a lower first conductivity type on the upper surface side of a support substrate 602. An n-type semiconductor layer 606 as a semiconductor layer, a first light-emitting layer 608, a p-type semiconductor layer 610 as a second conductive semiconductor layer, a second light-emitting layer 612 having the same emission wavelength as the first light-emitting layer 608, an upper first An n-type semiconductor layer 614 and an upper electrode 616 as one conductivity type semiconductor layer are sequentially provided, and a lower electrode 618 provided on the lower surface side of the support substrate 602, an upper first conductivity type semiconductor layer 614, and a second light emitting layer 612 are provided. A reference electrode 622 is provided in the penetrating recess 620 and electrically connected to the second conductivity type semiconductor layer 610. This element 600 is a wafer bonding type element formed by bonding a temporary substrate on which an epitaxial film including first and second light emitting layers 608 and 612 is grown and a support substrate 602, and is a support substrate side contact metal. The support substrate side bonding metal layer 632 formed through the layer 630 and the light emitting layer side bonding metal layer 628 are bonded, and the temporary substrate is removed or separated after bonding.

  As an example of mounting the element 600, the reference electrode 622 is connected to the positive electrode (+) terminal, and the lower electrode 618 is connected to the negative electrode (−) terminal. Then, a first circuit in which current flows from the reference electrode 622 through the first light emitting layer 608 to the intermediate electrode 604, the support substrate 602, and the lower electrode 618, and the reference electrode 622 through the second light emitting layer 612 to the upper side Two parallel circuits are formed: a second circuit through which current flows through the electrode 616 to the support substrate 602 and then to the lower electrode 618.

  Here, in the element 600, the recess 620 and the reference electrode 622 are provided in the central part of the element. The side surfaces of the stacked semiconductor layers 606 to 614 are coated with an insulating film, and the upper electrode 616 is disposed in a rectangular shape so as to surround the reference electrode 622, and is connected to the light emitting layer side bonding metal layer 628 from above the insulating coating. . Further, the central electrode 604 is disposed in a rectangular shape at the same position as the upper electrode 616 when viewed from the upper surface of the element. Therefore, the areas of the upper electrode 616 and the intermediate electrode 604 are equal. Therefore, the resistance component at each electrode portion in the first and second circuits can be made closer. Further, when the intermediate electrode 604, the upper electrode 616, and the reference electrode 622 are projected onto a virtual plane parallel to the upper surface of the support substrate 602, the distance between the reference electrode 622 and the intermediate electrode 604 and the relationship between the reference electrode 622 and the upper electrode 616 The distances are equal. That is, the projection positions of the upper electrode 616 and the intermediate electrode 604 in the vertical direction of the element are equal, and the reference electrode is located at the center portion inside these electrodes that are linearly provided in a rectangular shape. Therefore, the resistance component in the current path from the reference electrode 622 to the intermediate electrode 604 and the upper electrode 616 in the first and second circuits can be made closer.

  Since the first light emitting layer 608 is partly isolated by the insulating film 626 having protrusions, the effective areas of the first light emitting layer 108 and the second light emitting layer 112 are equal. Therefore, the resistance component in each light emitting layer in the first and second circuits can be made closer.

  That is, the element 600 has all the characteristic configurations of the first to third embodiments, and the characteristics of the semiconductor light emitting element can be improved more remarkably.

  The first light emitting layer 608 and the second light emitting layer 612 are preferably equal in thickness. Thereby, the resistance component in each light emitting layer in a 1st and 2nd circuit can be made equal, and the resistance component in a 1st and 2nd circuit can be brought closer.

  Making the thickness and / or composition of the n-type semiconductor layer 606, which is the lower first conductive semiconductor layer, and the n-type semiconductor layer 614, which is the upper first conductive semiconductor layer, equal in the first and second circuits The resistance component can be made closer, which is preferable.

  The element 600 includes a contact layer 624 in the middle of the p-type semiconductor layer 610 that is the second conductivity type semiconductor layer, and the p-type semiconductor layer 610 is divided into an upper layer 610a and a lower layer 610b with reference to the contact layer 624. The divided reference electrode 622 is disposed on the contact layer 624. At this time, it is preferable to make the resistance components in the first and second circuits closer by making the thicknesses of the upper layer 610a and the lower layer 610b equal.

  A suitable material, thickness, and the like of each component of the element 600 are the same as those in the first and fourth embodiments.

  In the present embodiment, both the intermediate electrode 604 and the upper electrode 616 are electrically connected to the support substrate 602. Specifically, not only the intermediate electrode 604 but also the upper electrode 616 is in contact with the light emitting layer side bonding metal layer 628. Therefore, the current of the second circuit including the second light emitting layer 612 is taken out from the lower electrode 618 via the light emitting layer side bonding metal layer 628 to the support substrate 602 through the side surface of the semiconductor layer. In this way, since both the first circuit and the second circuit extract current through the support substrate 602, the resistance difference between the two circuits is only the distance when the upper electrode 616 passes through the side surface of the semiconductor layer, and the upper circuit Since the electrode 616 has high conductivity, the difference is negligible. Therefore, in this embodiment, the resistance components of the first circuit and the second circuit can be made closer. In the case where the lower electrode 618 is provided on the lower surface side of the support substrate 602 as in this embodiment, the support substrate 602 is much thicker than the semiconductor layer, and even if it has conductivity, it has resistance compared to the electrode. This configuration is particularly effective because the may be relatively high.

  Furthermore, in the present embodiment, compared to the element 500, the trouble of connecting to the upper electrode at the time of mounting is omitted.

  An example of a method for manufacturing the element 600 will be described below by extracting only parts different from the first embodiment. In the manufacturing process of the element 600, the side surface exposure process and the insulating film formation process of the semiconductor layer are performed between the temporary substrate removal process (S7) and the upper electrode formation process (S8) of the first embodiment. In the exposing step, after forming a predetermined pattern with a photoresist, the side surfaces of the semiconductor layers 606 to 614 are exposed by mesa etching. In the insulating film forming step, an insulating film is formed by plasma CVD or sputtering, a predetermined pattern is formed with a photoresist, and then a part of the insulating film is removed. Other steps are the same as those in the first embodiment.

  The above description shows examples of representative embodiments, and the present invention is not limited to these embodiments. In addition, the present invention will be described below in more detail with reference to examples, but the present invention is not limited to the following examples.

  Further, in the following examples, evaluation is performed in the case where a current is simultaneously supplied to two parallel circuits of the first circuit and the second circuit, but by separately supplying a current to the first circuit and the second circuit, The element of the present invention can be inspected by separately evaluating and comparing the characteristics of the first circuit (forward voltage, wavelength, etc.) and the characteristics of the second circuit (forward voltage, wavelength, etc.). it can.

  The semiconductor light emitting device of each embodiment shown in FIGS. 1 to 6 was made as a prototype and performance was evaluated, and will be described below.

Example 1
The semiconductor light emitting device 100 according to the present invention was manufactured by the method described in the first embodiment. First, AuGe / Ni / Au (thickness: 800 nm) is formed as a support substrate-side contact metal layer on an n-type GaAs substrate (thickness: 350 μm) by a resistance heating vapor deposition method at 400 to 450 ° C. in a nitrogen atmosphere. An alloying treatment was performed by heating. Thereafter, Ti / Au (thickness: 100 nm / 1 μm) was formed on the metal layer as a support substrate-side bonding metal layer by resistance heating vapor deposition.

Next, an upper n-type semiconductor layer (Al _0.3 Ga _0.7 As, thickness: 5 μm, dopant: Te), second light emitting layer (GaAs) is formed on an n-type GaAs substrate as a temporary substrate by MOCVD. Well structure / Al _0.2 Ga _0.8 As barrier, thickness: 8 nm / 6 nm), p-type semiconductor layer (upper layer, Al _0.2 Ga _0.8 As, thickness: 3 μm, dopant: C), p-type contact layer (Al _0.5 Ga _0.5 As, thickness: 200 nm, dopant: Zn), p-type semiconductor layer (lower layer, Al _0.2 Ga _0.8 As, thickness: 3 μm, dopant) : C), first light emitting layer (GaAs well structure / Al _0.2 Ga _0.8 As barrier, thickness: 8 nm / 6 nm), lower n-type semiconductor layer (Al _0.3 Ga _0.7 As, thickness) Sequentially epitaxial: 5 μm, dopant: Te) Length allowed was. The compositions and film thicknesses of the first light emitting layer and the second light emitting layer were equal, and the emission peak wavelength from the first light emitting layer and the second light emitting layer was 850 nm. The p-type semiconductor layer, the light emitting layer, and the n-type semiconductor layer are all designed to be equally symmetric with respect to the composition on the upper and lower sides with the p-type contact layer as the center.

Next, a predetermined pattern was formed on the lower n-type semiconductor layer with a photoresist (manufactured by Tokyo Ohka Kogyo Co., Ltd., OFPR800, hereinafter the same), and then a groove penetrating to the first light emitting layer was formed by etching. The etching solution was NH ₄ OH: H ₂ O ₂ : H ₂ O = 1: 1: 20 (volume ratio). After removing the resist, SiN is formed as an insulating film by plasma CVD, and a circular pattern with the groove as the outer periphery is formed with a photoresist. Then, the insulating film other than the circular portion is removed by etching with a BHF solution, and protrusions are formed. An insulating film including the same was formed.

Next, AuGe / Ni / Au (thickness: 800 nm) is formed as an intermediate electrode on the lower n-type semiconductor layer by resistance heating vapor deposition, and Ti / Au (thickness) is further formed as a light emitting layer-side bonding metal layer. : 100 nm / 1 μm). Then, the light emitting layer side joining metal layer and the support substrate side joining metal layer were adhere | attached, and the temporary board | substrate and the support substrate were joined by thermocompression bonding at 400 degreeC for 60 minutes. Thereafter, the temporary substrate was removed with an etching solution of NH ₄ OH: H ₂ O ₂ : H ₂ O = 8: 100: 100 (volume ratio).

Next, AuGe / Ni / Au (thickness: 800 nm) and Ti / Au (thickness: 100 nm / 1 μm) are formed on the upper semiconductor layer by resistance heating vapor deposition, and a pattern is formed using a photoresist. The upper electrode was formed by etching with an HF aqueous solution of iodine-based etchant and stripping the resist. Further, after forming a protective pattern other than a portion that becomes a concave portion with a photoresist, the concave portion was formed with an etching solution of NH ₄ OH: H ₂ O ₂ : H ₂ O = 8: 100: 100 (volume ratio). At this time, the p-type contact layer was used as an etching stop layer. Next, a reference electrode was formed in the recess. Specifically, a pattern protecting a portion other than the electrode forming portion is formed with a photoresist, AuZn (thickness: 300 nm) and Ti / Au (thickness: 100 nm / 1 μm) are formed by electron beam evaporation, and acetone is added. -It was immersed in dimethyl sulfoxide, the resist was swollen, and the metal on the resist was removed together with the resist to form a reference electrode.

Next, AuGe / Ni / Au (thickness: 800 nm) is formed as a lower electrode on the back surface of the support substrate by resistance heating vapor deposition, and the alloying treatment is performed by heating at 400 to 450 ° C. in a nitrogen atmosphere. went. Finally, dicing was performed to produce an LED element using the semiconductor light emitting element 100. The dimensions of the LED element thus fabricated are as follows.
Chip size in FIG. 1B: 320 μm square upper electrode size r (n): 90 μm
Reference electrode size r (p): 80 μm
Opening diameter of recess: 100 μm
Diameter of the portion where the second light emitting layer is removed by the recess: 90 μm
Diameter of groove formation outer periphery by insulating film: 90 μm
Therefore, the effective areas of the first light emitting layer and the second light emitting layer are equal.

(Example 2)
A semiconductor light emitting device 200 according to the present invention was manufactured by the method described in the second embodiment. Only the steps different from those in Example 1 will be described. In this embodiment, the groove forming step is not performed, and thereafter, a SiN film is formed as an insulating film on the lower n-type semiconductor layer by a plasma CVD method, and a pattern having a circular recess having a diameter r (n2) is formed with a photoresist. Then, the circular insulating film was removed by etching with an iodine-based etchant to form an insulating film. Other steps are the same as those in the first embodiment. The dimensions of the LED element thus fabricated are as follows.
Chip size in FIG. 2B: 320 μm square upper electrode size r (n1): 90 μm
Intermediate electrode size r (n2): 90 μm
Therefore, the areas of the upper electrode and the intermediate electrode are equal.
Reference electrode size r (p): 80 μm
Opening diameter of recess: 100 μm
L1 = L2 = 180 μm
Therefore, the distances of the upper electrode and the intermediate electrode from the reference electrode are equal.

(Example 3)
A semiconductor light emitting device 300 according to the present invention was manufactured by the method described in the third embodiment. That is, the individual manufacturing process is the same as that of Example 2, and the dimensions of the LED element thus produced are as follows.
Chip size in FIG. 3B: 320 μm square upper electrode size r (n1): 90 μm
Intermediate electrode size r (n2): 30 μm
Reference electrode size r (p): 80 μm
Opening diameter of recess: 100 μm
Since the electrode centers of the upper electrode and the intermediate electrode coincide with each other when viewed from the upper surface of the element, the distance from the reference electrode of both electrodes in FIG. 3B and the position when projected in the vertical direction are equal.

Example 4
A semiconductor light emitting device 400 according to the present invention was manufactured by the method described in the fourth embodiment. It was produced by the same process as in Example 2 except that the pattern shape in the intermediate process was changed. The upper electrode 416 and the pad electrode 417 were formed as described above.
The dimensions of the LED element thus produced are as follows.
Chip size in FIG. 4B: 320 μm square upper pad electrode size r (n1): 90 μm
Reference electrode size r (p): 80 μm
Opening diameter of recess: 100 μm
Area of rectangular upper electrode = total area of plural intermediate electrodes = 4800 μm ²
Therefore, the areas of the upper electrode and the intermediate electrode are equal.

(Example 5)
A semiconductor light emitting device 500 according to the present invention was manufactured by the method described in the fifth embodiment. That is, the individual manufacturing steps are the same as those in Example 1 and Example 4, and the dimensions of the LED elements thus prepared are as follows.
Chip size in FIG. 5B: 320 μm square upper pad electrode size r (n1): 90 μm
Reference electrode size r (p): 80 μm
Opening diameter of recess: 100 μm
Diameter of the portion where the second light emitting layer is removed by the recess: 90 μm
Diameter of groove formation outer periphery by insulating film: 90 μm
Therefore, the effective areas of the first light emitting layer and the second light emitting layer are equal.
Area of rectangular upper electrode = total area of plural intermediate electrodes = 4800 μm ²
Therefore, the areas of the upper electrode and the intermediate electrode are equal.

(Example 6)
A semiconductor light emitting device 600 according to the present invention was manufactured by the method described in the sixth embodiment. Only the steps different from those in Example 1 will be described. In this embodiment, a side surface exposure step and an insulating film formation step are performed between the temporary substrate removal step and the upper electrode formation step. In the exposure process, after a predetermined pattern is formed with a photoresist, mesa etching is performed with an etching solution of H ₃ PO ₄ : H ₂ O ₂ : H ₂ O = 1: 1: 4 (volume ratio), and the side surface of the semiconductor layer Was exposed. In the insulating film forming step, SiN was formed as an insulating film by a plasma CVD method, a predetermined pattern was formed with a photoresist, and then a part of the insulating film was removed by etching with a BHF solution. Other steps are the same as those in the first embodiment. The dimensions of the LED element thus fabricated are as follows.
Chip size in FIG. 6B: 320 μm Four-sided reference electrode size r (p): 80 μm
Opening diameter of recess: 100 μm
Diameter of the portion where the second light emitting layer is removed by the recess: 90 μm
Diameter of groove formation outer periphery by insulating film: 90 μm
Therefore, the effective areas of the first light emitting layer and the second light emitting layer are equal. In addition, since the effective regions of the upper electrode and the intermediate electrode (regions in contact with the upper n-type semiconductor layer and the lower n-type semiconductor layer, respectively) overlap completely when viewed from above, the areas of both electrodes are equal, and the reference electrode The distance from and the position when projected in the vertical direction are also equal. Furthermore, since the upper electrode is connected to the support substrate through the side surface of the semiconductor layer via the insulating film, both the first circuit and the second circuit take out current through the support substrate. Therefore, in Example 6, the resistances in the first circuit and the second circuit were equal, and an equivalent parallel circuit was made.

(Comparative Example 1)
A semiconductor light emitting device 700 shown in FIG. 7 was manufactured in the same manner as in Example 1 except that the groove forming step and the subsequent insulating film forming step were not performed. As shown in FIG. 7A, the element 700 includes an intermediate electrode (light emitting layer side contact metal layer) 704, an n type semiconductor layer 706 as a lower first conductive type semiconductor layer, on the upper surface side of the support substrate 702, The first light emitting layer 708, the p-type semiconductor layer 710 as the second conductive type semiconductor layer, the second light emitting 712 having the same emission wavelength as the first light emitting layer 708, and the n type semiconductor layer as the upper first conductive type semiconductor layer 714 and an upper electrode 716 sequentially, provided in a lower electrode 718 provided on the lower surface side of the support substrate 702, and in a recess 720 penetrating the upper first conductive type semiconductor layer 714 and the second light emitting layer 712, and second conductive And a reference electrode 722 electrically connected to the type semiconductor layer 710. Bonding is performed between the support substrate-side bonding metal layer 732 formed via the support substrate-side contact metal layer 730 and the light emitting layer-side bonding metal layer 728. A contact layer 724 is provided in the middle of the p-type semiconductor layer 710. The p-type semiconductor layer 710 is divided into an upper layer 710a and a lower layer 710b on the basis of the contact layer 724, and a reference electrode 722 is disposed on the contact layer 724. ing.

The dimensions of the LED element thus fabricated are as follows.
Chip size in FIG. 7B: 320 μm square upper electrode size r (n): 90 μm
Reference electrode size r (p): 80 μm
Opening diameter of recess: 100 μm
Diameter of the portion where the second light emitting layer is removed by the recess: 90 μm
Therefore, the effective area of the first light emitting layer is larger than the effective area of the second light emitting layer by the area from which the second light emitting layer is removed (equivalent to 6% of the effective area of the first light emitting layer). The area of the intermediate electrode is 102400 μm ² and is much larger than the area of the upper electrode.

(Comparative Example 2)
A semiconductor light emitting device similar to that of Comparative Example 1 was produced except that the light emitting layer was one layer. That is, as a semiconductor layer, an n-type semiconductor layer (Al _0.3 Ga _0.7 As, thickness: 5 μm, dopant: Te) and a light emitting layer (GaAs well structure / Al _0.2 Ga _{0. 8} As barrier, thickness: 8 nm / 6 nm), and a p-type semiconductor layer (Al _0.2 Ga _0.8 As, thickness: 3 μm, dopant: C) were sequentially epitaxially grown. The emission peak wavelength from the light emitting layer was 850 nm. Further, since the light emitting layer is a single layer, the recess forming step and the reference electrode forming step are unnecessary. An upper electrode (diameter 80 μm) was formed in the central portion on the p-type semiconductor layer. Since the upper electrode is in contact with the p-layer, AuZn (thickness: 500 nm) was used.

  (Evaluation method)

  The forward voltage Vf when a current of 20 mA was passed to the obtained semiconductor light emitting device using a constant current voltage power source and the light emission output Po by the integrating sphere were measured. The light output was measured using a total luminous flux spectroscopic measurement system (SLMS-1021-S manufactured by Labshere). Further, a large current was gradually applied to each semiconductor light emitting element, and a current value (maximum current value) when the light output reached the maximum (maximum light emission output) was obtained. These results are shown in Table 1 and FIG.

(Evaluation results)
As shown in Table 1, when Comparative Example 2 and Comparative Example 1 are compared, the maximum current value and forward voltage are slightly improved and the light emission output is substantially changed by changing the light emitting layer from one layer to two layers. Therefore, the improvement in characteristics as expected to be obtained by making the light emitting layer into two layers could not be obtained. As shown in FIGS. 1 and 3, when Comparative Example 1 is compared with Examples 1 to 6, the resistance components of the current circuit including the first light emitting layer and the current circuit including the second light emitting layer are made closer to each other. By devising the element structure, the maximum current value and the maximum light emission output could be remarkably improved while maintaining the forward voltage substantially.

  According to the present invention, in a semiconductor light emitting device having two light emitting layers having the same emission peak wavelength, the resistance components of the current circuit including the first light emitting layer and the current circuit including the second light emitting layer are made closer to each other. Further, by devising the element structure, it is possible to obtain a high maximum current value and light emission output with a low forward voltage.

100 to 600 Semiconductor light emitting device 102 Support substrate 104 Intermediate electrode 106 N-type semiconductor layer (lower first conductive semiconductor layer)
108 1st light emitting layer 110 p-type semiconductor layer (2nd conductivity type semiconductor layer)
110a Upper layer
110b Lower layer 112 Second light emitting layer 114 n-type semiconductor layer (upper first conductivity type semiconductor layer)
116 Upper electrode 118 Lower electrode 120 Recessed portion 122 Reference electrode 124 Contact layer 126 Insulating film

Claims (24)

An intermediate electrode, a lower first conductive type semiconductor layer, a first light emitting layer, a second conductive type semiconductor layer, a second light emitting layer having the same emission wavelength as the first light emitting layer, an upper first side, Comprising one conductive type semiconductor layer and an upper electrode in sequence,
A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
A part of an effective region through which the current of the first light emitting layer flows is regulated ;
The semiconductor light emitting device characterized and this is equal to the area of the upper electrode and the intermediate electrode.   The semiconductor light emitting device according to claim 1, wherein effective areas of the first light emitting layer and the second light emitting layer are equal. An intermediate electrode, a lower first conductive type semiconductor layer, a first light emitting layer, a second conductive type semiconductor layer, a second light emitting layer having the same emission wavelength as the first light emitting layer, an upper first side, Comprising one conductive type semiconductor layer and an upper electrode in sequence,
A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
A portion of the intermediate electrode is regulated;
The semiconductor light emitting device characterized and this is equal to the area of the upper electrode and the intermediate electrode.   4. The semiconductor light emitting device according to claim 3, wherein when the intermediate electrode and the upper electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the projection positions of the intermediate electrode and the upper electrode overlap at least partially. element. When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are as follows: The semiconductor light emitting element of Claim 3 or 4 which is equal. An intermediate electrode, a lower first conductive type semiconductor layer, a first light emitting layer, a second conductive type semiconductor layer, a second light emitting layer having the same emission wavelength as the first light emitting layer, an upper first side, Comprising one conductive type semiconductor layer and an upper electrode in sequence,
A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
A part of an effective region through which the current of the first light emitting layer flows is regulated;
A portion of the intermediate electrode is regulated;
When projecting the intermediate electrode and the upper electrode onto a virtual plane parallel to the upper surface of the support substrate, the projection positions of the intermediate electrode and the upper electrode at least partially overlap ,
The semiconductor light emitting device characterized and this is equal to the area of the upper electrode and the intermediate electrode. The thickness of the said 1st light emitting layer and the said 2nd light emitting layer is equal, The thickness of the said lower 1st conductivity type semiconductor layer and the said upper 1st conductivity type semiconductor layer is any one of Claims 1-6. The semiconductor light-emitting device described in 1. The semiconductor light-emitting device according to any one of the lower first conductive type semiconductor layer and the upper first conductive semiconductor layer according to claim 1 to 7 composition equal. A contact layer is provided in the middle of the second conductivity type semiconductor layer, and the second conductivity type semiconductor layer is divided into an upper layer and a lower layer of the contact layer,
The semiconductor light-emitting device according to any one of claim 1 to 8 wherein said reference electrode is disposed on the contact layer. The semiconductor light emitting element according to claim 9 , wherein the upper layer and the lower layer have the same thickness. The semiconductor light-emitting device according to any one of claim 1 to 10 having a lower electrode that mediates electrical connection to the outside of the intermediate electrode. The intermediate electrode and the semiconductor light emitting device according to any one of claims 1 to 11, wherein the upper electrode is electrically connected together to the supporting substrate. On the temporary substrate, the upper first conductive semiconductor layer, the second light emitting layer, the second conductive semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive semiconductor layer Sequentially forming
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Restricting a part of the effective region through which the current of the first light emitting layer flows ;
A method of manufacturing a semiconductor light emitting device, wherein the upper electrode and the intermediate electrode have the same area . On the temporary substrate, the upper first conductive semiconductor layer, the second light emitting layer, the second conductive semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive semiconductor layer Sequentially forming
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Regulating a portion of the intermediate electrode ;
A method of manufacturing a semiconductor light emitting device, wherein the upper electrode and the intermediate electrode have the same area . The semiconductor light-emitting element according to claim 14 , wherein when the intermediate electrode and the upper electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the projection positions of the intermediate electrode and the upper electrode overlap at least partially. Production method. When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are determined. The method for manufacturing a semiconductor light emitting device according to claim 14 , wherein the semiconductor light emitting device is made equal. On the temporary substrate, the upper first conductive semiconductor layer, the second light emitting layer, the second conductive semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive semiconductor layer Sequentially forming
Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
Removing or separating the temporary substrate;
Forming an upper electrode on the upper first conductive semiconductor layer;
Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
Restricting a part of the effective region through which the current of the first light emitting layer flows;
Regulating a portion of the intermediate electrode;
When projecting the intermediate electrode and the upper electrode on a virtual plane parallel to the upper surface of the support substrate, at least partially overlap the projection position of the intermediate electrode and the upper electrode ,
The method of manufacturing a semiconductor light emitting element characterized that you equal the area of the upper electrode and the intermediate electrode.   An intermediate electrode, a lower first conductive type semiconductor layer, a first light emitting layer, a second conductive type semiconductor layer, a second light emitting layer having the same emission wavelength as the first light emitting layer, an upper first side, Comprising one conductive type semiconductor layer and an upper electrode in sequence,
  A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
  A portion of the intermediate electrode is regulated;
  When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are as follows: A semiconductor light emitting element characterized by being equal.   An intermediate electrode, a lower first conductive type semiconductor layer, a first light emitting layer, a second conductive type semiconductor layer, a second light emitting layer having the same emission wavelength as the first light emitting layer, an upper first side, Comprising one conductive type semiconductor layer and an upper electrode in sequence,
  A reference electrode provided in a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer and electrically connected to the second conductive semiconductor layer;
  A part of an effective region through which the current of the first light emitting layer flows is regulated;
  A portion of the intermediate electrode is regulated;
  When projecting the intermediate electrode and the upper electrode onto a virtual plane parallel to the upper surface of the support substrate, the projection positions of the intermediate electrode and the upper electrode at least partially overlap,
  When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are as follows: A semiconductor light emitting element characterized by being equal.   The semiconductor light emitting device according to claim 18, wherein effective areas of the first light emitting layer and the second light emitting layer are equal.   On the temporary substrate, the upper first conductive semiconductor layer, the second light emitting layer, the second conductive semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive semiconductor layer Sequentially forming
  Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
  Removing or separating the temporary substrate;
  Forming an upper electrode on the upper first conductive semiconductor layer;
  Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
  Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
  Restricting a part of the effective region through which the current of the first light emitting layer flows;
  When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are determined. A method of manufacturing a semiconductor light emitting device, characterized in that they are equal.   On the temporary substrate, the upper first conductive semiconductor layer, the second light emitting layer, the second conductive semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive semiconductor layer Sequentially forming
  Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
  Removing or separating the temporary substrate;
  Forming an upper electrode on the upper first conductive semiconductor layer;
  Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
  Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
  Regulating a portion of the intermediate electrode;
  When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are determined. A method of manufacturing a semiconductor light emitting device, characterized in that they are equal.   On the temporary substrate, the upper first conductive semiconductor layer, the second light emitting layer, the second conductive semiconductor layer, the first light emitting layer having the same emission wavelength as the second light emitting layer, and the lower first conductive semiconductor layer Sequentially forming
  Sequentially providing an intermediate electrode and a support substrate on the surface of the lower first conductive semiconductor layer;
  Removing or separating the temporary substrate;
  Forming an upper electrode on the upper first conductive semiconductor layer;
  Providing a recess penetrating the upper first conductive semiconductor layer and the second light emitting layer;
  Forming a reference electrode electrically connected to the second conductivity type semiconductor layer in the recess,
  Restricting a part of the effective region through which the current of the first light emitting layer flows;
  Regulating a portion of the intermediate electrode;
  When projecting the intermediate electrode and the upper electrode on a virtual plane parallel to the upper surface of the support substrate, at least partially overlap the projection position of the intermediate electrode and the upper electrode,
  When the intermediate electrode, the upper electrode, and the reference electrode are projected onto a virtual plane parallel to the upper surface of the support substrate, the distance between the reference electrode and the intermediate electrode and the distance between the reference electrode and the upper electrode are determined. A method of manufacturing a semiconductor light emitting device, characterized in that they are equal.   24. The method of manufacturing a semiconductor light emitting element according to claim 21, wherein effective areas of the first light emitting layer and the second light emitting layer are equalized.

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