JP5153082B2 - Semiconductor element - Google Patents

Description

  The present invention relates to a semiconductor element in which a semiconductor layer is bonded to a conductive substrate.

  Currently, there is a semiconductor device manufactured by sequentially growing a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer including a nitride-based semiconductor layer on an inexpensive sapphire substrate instead of an expensive GaN substrate. Are known. When the semiconductor layer is grown on the sapphire substrate in this manner, the sapphire substrate is insulative, and thus an electrode that is electrically connected to the first conductivity type semiconductor layer cannot be formed on the back surface of the sapphire substrate. Therefore, the second conductive semiconductor layer and the active layer are partially removed by etching or the like so that a part of the first conductive semiconductor layer is exposed, and then an electrode is formed on the exposed first conductive semiconductor layer. ing. When the electrodes are formed in this way, the electrodes formed in the first conductive type semiconductor layer and the second conductive type semiconductor layer are formed on the same orientation surface. A flip chip system is adopted in which the formed surface is the bottom surface and light is irradiated from the surface where no electrode is formed.

  However, in such a flip-chip method, when assembling the semiconductor light emitting element as a light emitting device, both electrodes are formed on the same orientation surface. This causes a problem such as a decrease in assembly yield. Further, since the sapphire substrate has low thermal conductivity, there is a problem that heat generated when a large current is passed through the semiconductor light emitting element cannot be sufficiently released, and the semiconductor light emitting element is likely to deteriorate.

  Therefore, a semiconductor element manufactured by replacing a semiconductor layer grown on an inexpensive insulating substrate such as a sapphire substrate with a conductive substrate and a manufacturing method thereof are known.

For example, in the method for manufacturing a semiconductor device described in Patent Document 1, after a semiconductor layer including a nitride-based semiconductor layer is grown on a sapphire substrate, an ohmic electrode is formed over one entire surface of the semiconductor layer. Next, a conductive substrate made of p-type GaAs or the like having high thermal conductivity is bonded onto the ohmic electrode through the conductive adhesive layer, and then the sapphire substrate is separated. Then, the p-side electrode and the n-side electrode are opposed to each other by forming the p-side electrode and the n-side electrode on the exposed surface of the conductive substrate and the surface of the semiconductor layer exposed by separating the sapphire substrate, respectively. A semiconductor element formed on the surface is manufactured. As described above, in the semiconductor element of Patent Document 1, by providing both electrodes on the opposing surfaces, the alignment during assembly can be simplified, so that the assembly yield can be improved. In addition, by adhering a semiconductor layer on a conductive substrate having high thermal conductivity, heat dissipation was improved, and deterioration of the semiconductor light emitting element due to heat or the like during voltage application could be suppressed.
Japanese Patent Laid-Open No. 9-8403

  However, the semiconductor element disclosed in Patent Document 1 has a problem that the operating voltage gradually increases as the driving time increases.

  The present invention has been made in view of such a problem, and an object thereof is to provide a semiconductor element capable of suppressing an increase in operating voltage.

  A semiconductor device according to the present invention includes a semiconductor layer including an active layer including a nitride-based semiconductor, a conductive substrate to which the semiconductor layer is bonded via a conductive adhesive layer, and the conductive substrate of the semiconductor layer. An ohmic electrode provided on one opposing surface, an insulating film provided between the ohmic electrode and the conductive adhesive layer, covering the ohmic electrode, and penetrating the insulating film, the ohmic electrode and the conductive A connection electrode for electrically connecting to the conductive substrate, the ohmic electrode is provided by exposing a part of one surface of the semiconductor layer, and the insulating film is exposed from the ohmic electrode The semiconductor layer is provided so as to cover one surface of the semiconductor layer.

  In addition, a reflective film insulated from the ohmic electrode by the insulating film is provided between the ohmic electrode and the conductive adhesive layer, and light emitted from the active layer is emitted from the semiconductor layer. It is characterized in that it is taken out from the surface opposite to the surface facing the reflective film.

  The insulating film has a dielectric multilayer film capable of reflecting light emitted from the active layer, and the light emitted from the active layer faces the insulating film of the semiconductor layer. It is taken out from the opposite surface to the outside.

  In the present invention, since the ohmic electrode is provided so as to partially expose the semiconductor layer, the contact area between the semiconductor layer and the ohmic electrode can be reduced as compared with the conventional case. For this reason, the influence of the migration of the ohmic electrode material caused by energization for driving can be suppressed. In addition, it is possible to suppress deterioration in characteristics of the contact interface between the semiconductor layer and the ohmic electrode, which is caused by heat when the semiconductor layer is bonded to the conductive substrate with the conductive adhesive layer. As a result, according to the present invention, it is possible to suppress an increase in operating voltage accompanying an increase in driving time.

  Also, by covering the ohmic electrode with an insulating film having low thermal conductivity, the heat conducted from the conductive adhesive layer to the ohmic electrode can be reduced when the semiconductor layer is bonded to the conductive substrate via the conductive adhesive layer. Can be suppressed. Thereby, deterioration at the interface between the semiconductor layer and the ohmic electrode due to heat can be further suppressed.

  Further, by electrically insulating the reflective film from the ohmic electrode, current can be prevented from flowing through the reflective film. Therefore, since the influence of the migration of the reflective film material due to energization can be reduced, the area of the reflective film can be provided as wide as the area of the semiconductor layer. Therefore, it is possible to increase the amount of light extracted outside while suppressing an increase in operating voltage. Moreover, since the influence of the migration of the reflective film material can be reduced by making the insulating film a dielectric multilayer film structure capable of reflecting the light emitted from the active layer, the same effect can be obtained.

(First reference form)
Hereinafter, a semiconductor device (light emitting diode) of a first reference embodiment according to the present invention will be described with reference to the drawings. Figure 1 is a cross-sectional view of a semiconductor device according to the first reference embodiment. FIG. 2 is a plan view taken along line II-II in FIG.

  As shown in FIG. 1, a semiconductor element 1 includes a p-side connection electrode 4, an insulating film 5, and a p-side ohmic contact on a conductive substrate 2 (corresponding to the substrate of the claims) via a conductive adhesive layer 3. The electrode 6, the p-type contact layer 7, the p-type cladding layer 8, the p-type cap layer 9, the active layer 10, the n-type cladding layer 11, the n-type contact layer 12, and the n-side electrode 13 are sequentially stacked.

The semiconductor layer of this preferred embodiment is composed of a stacked structure of p-type contact layer 7~n type contact layer 12. Note that the structure of the semiconductor layer is not limited to such a structure, and any structure having a p-type layer, an active layer having a nitride-based semiconductor, and an n-type layer may be used. For example, the p-type contact layer and the p-type cladding layer may have a single layer structure having the functions of both the contact layer and the cladding layer, or may have a layer structure of three or more layers. Further, the n-type contact layer and the n-type cladding layer may have a single layer structure having the functions of both the contact layer and the cladding layer, or may have a layer structure of three or more layers. Further, the p-type cap layer may not be provided.

  Moreover, you may provide the electrode for electricity supply in the back surface of the electroconductive board | substrate 2 as needed.

The conductive substrate 2 is made of a Ge substrate having conductivity. The conductive substrate 2 is not limited to a Ge substrate, and a conductive substrate made of GaP, Si, GaAs, InP, SiC, ZrB ₂ , Cu—W, Fe—Ni or the like may be applied. it can.

  The conductive adhesive layer 3 is made of Au—Sn, and is used for bonding the layers 4 to 12 to the conductive substrate 2 and electrically connects the p-side connection electrode 4 and the conductive substrate 2. Is for. Note that a material such as Au—Ge, Sn, In, and Pb—Sn can be applied to the conductive adhesive layer 3.

  The p-side connection electrode 4 is formed so as to be electrically connected to a connection portion 6c of a p-side ohmic electrode 6 described later. The p-side connection electrode 4 is configured by, for example, an Au layer having a thickness of about 2000 nm, a Pd layer having a thickness of about 150 nm, and a Ti layer having a thickness of about 30 nm stacked in this order from the conductive substrate 2 side. The structure is not limited to this.

The insulating film 5 is formed so as to cover the p-side ohmic electrode 6, and an electrode opening 5 a in which the p-side connection electrode 4 is embedded is formed at a position corresponding to the connection portion 6 c of the p-side ohmic electrode 6. Is formed. The insulating film 5 is made of a SiO ₂ film of about 380 nm. As a material constituting the insulating film 5, oxides such as TiO ₂ , Ta ₂ O ₅ , Al ₂ O ₃ , ZrO ₂ , Nb ₂ O ₅ , HfO ₂ , and nitrides such as SiN may be applied. it can.

  On the p-side ohmic electrode 6, a Ti layer having a thickness of about 10 nm, an Au layer having a thickness of about 100 nm, and a Pd layer having a thickness of about 20 nm are sequentially stacked from the conductive substrate 2 side. In addition, the metal material which comprises the p side ohmic electrode 6 is not specifically limited, However, It is desirable to apply the metal with little light absorption. In addition, it is preferable to apply a metal having good ohmic characteristics to the p-type contact layer 7 to a portion in contact with the p-type contact layer 7.

  Here, as shown in FIG. 2, the p-side ohmic electrode 6 includes a plurality of stripe portions 6 a, a connection portion 6 b that connects the stripe portions 6 a, and a connection portion 6 c to which the p-side connection electrode 4 is connected. Have The stripe portions 6a have a width of about 2 μm and are periodically arranged at intervals of about 6 μm. Openings 6d are formed between the stripe portions 6a, and the p-type contact layer 7 is exposed. The connecting portion 6c is formed in a rectangular shape having a side length of about 100 μm. The insulating film 5 is also formed on the p-type contact layer 7 exposed from the p-side ohmic electrode 6.

  The p-type contact layer 7 is composed of a p-type GaN layer doped with a p-type impurity such as Mg. The p-type cladding layer 8 and the p-type cap layer 9 are made of a p-type AlGaN layer doped with a p-type impurity such as Mg.

  The active layer 10 has an MQW structure (multiple quantum well structure) including a well layer made of an InGaN layer and a barrier layer.

  The n-type cladding layer 11 is composed of an n-type AlGaN layer doped with an n-type impurity such as Si. The n-type contact layer 12 is composed of an n-type GaN layer doped with an n-type impurity such as Si.

  The n-side electrode 13 is composed of a plurality or a single metal layer or a transparent conductive oxide layer. The n-side electrode 13 is desirably arranged so as not to hinder the progress of light irradiated to the outside. When the n-side electrode 13 is formed of a metal layer, it may be thin enough to transmit light. Further, it is desirable to form a pad electrode (not shown) for connecting a gold wire on the n-side electrode 13.

  In this semiconductor element 1, when a voltage is applied to the n-side electrode 13 and the conductive substrate 2, electrons are injected into the active layer 10 through the n-type semiconductor layers 11 and 12, and an opening 6d is formed. Holes are injected into the active layer 10 through the p-side ohmic electrode 6 and the p-type semiconductor layers 7 to 9. The electrons and holes injected into the active layer 10 combine to emit light, and light is emitted from the n-type contact layer 12 side.

  Next, a method for manufacturing the above-described semiconductor element will be described with reference to the drawings. 3-10 is sectional drawing in each manufacturing process of a semiconductor element.

  First, as shown in FIG. 3, after growing a buffer layer 22 made of AlGaN or GaN on the C (0001) plane of a growth substrate 21 made of a sapphire substrate, an undoped GaN layer 23 is formed on the buffer layer 22. Form. A substrate capable of growing a nitride-based semiconductor can be used as the growth substrate 21 instead of the sapphire substrate. For example, a substrate made of SiC, Si, GaAs, MgO, ZnO, spinel, GaN, or the like can be used as the growth substrate 21. Next, the n-type contact layer 12, the n-type cladding layer 11, the active layer 10, the p-type cap layer 9, the p-type cladding layer 8, and the p-type contact layer 7 are sequentially grown on the GaN layer 23. Thereafter, the acceptor is activated by heat treatment, electron beam treatment, or the like, and the p-type semiconductor layers 7 to 9 are made to be p-type.

  Next, as shown in FIG. 4, a Pd layer, an Au layer, and a Ti layer are sequentially stacked on the p-type contact layer 7 by using an electron beam evaporation method and a lithography technique, and then patterned to form a stripe portion 6 a. Then, the p-side ohmic electrode 6 having the connecting portion 6b, the connecting portion 6c, and the opening 6d is formed.

Next, as shown in FIG. 5, after an insulating film 5 made of a SiO ₂ film is formed by an electron beam evaporation method or a sputtering method, it corresponds to the p-side connection electrode 4 using a lithography technique and an etching technique. The portion is removed to form an electrode opening 5a.

  Next, as shown in FIG. 6, the p-side connection electrode 4 in which a Ti layer, a Pd layer, and an Au layer are sequentially stacked is formed by using an electron beam vapor deposition method or a resistance heating vapor deposition method and a lithography technique. It forms so that it may be electrically connected with the connection part 6c of the side ohmic electrode 6. FIG.

  Next, as shown in FIG. 7, the conductive substrate 2 made of Ge is bonded onto the p-side connection electrode 4 and the insulating film 5 through the heated conductive adhesive layer 3.

  Next, as shown in FIG. 8, the growth substrate 21 is peeled off using a laser lift-off method. The growth substrate 21 may be peeled off using a technique such as polishing, dry etching, or wet etching. Further, when a growth substrate made of Si and GaAs is used instead of the growth substrate 21 made of a sapphire substrate, it is desirable to peel off the growth substrate by wet etching.

Next, as shown in FIG. 9, after removing the buffer layer 22 and the GaN layer 23 to expose the n-type contact layer 12, the n-side electrode 13 is formed in a predetermined region of the n-type contact layer 12. In order to improve the light extraction efficiency, the n-side electrode 13 is formed after performing fine processing such as forming irregularities on the surface of the n-type contact layer 12 where the n-side electrode 13 is formed. May be. This fine processing may be performed on SiO ₂ or SiN formed on the n-type contact layer 12.

  Finally, as shown in FIG. 10, element isolation is performed by a dicing blade or the like, and the semiconductor element 1 is completed. In addition, in order to suppress damage to the semiconductor layers 7 to 12 such as the active layer 10, element isolation may be performed with a dicing blade after partial etching of a region to be separated of the conductive substrate 2 is performed.

  Here, an experiment on the operating voltage conducted by the inventor of the present invention will be described. In this experiment, a comparative semiconductor element having the same configuration except that the above-described p-side ohmic electrode was formed over the entire surface between the insulating film and the p-type contact layer was used. And the operating voltage at the time of sending an electric current through the semiconductor element 1 by this invention and the semiconductor element for a comparison was measured. FIG. 11 shows current-voltage characteristics of the semiconductor element 1 of the present invention and a comparative semiconductor element obtained by experiment. In FIG. 11, the solid line shows the experimental result of the semiconductor element 1 of the present invention, and the dotted line shows the experimental result of the comparative semiconductor element.

  As shown in FIG. 11, when compared with the same current, it can be seen that the operating voltage of the semiconductor element 1 according to the present invention is lower than the operating voltage of the semiconductor element for comparison. For example, when a current of about 20 mA is passed, the operating voltage of the semiconductor element 1 according to the present invention is about 3.65 V, whereas the operating voltage of the semiconductor element for comparison is the operation voltage of the semiconductor element 1 according to the present invention. The voltage was about 3.83 V, which was about 0.18 V higher than the voltage. As a result, it can be seen that the semiconductor element 1 of the present invention can reduce the operating voltage by forming the opening 6d in the p-side ohmic electrode 6 as compared with the comparative semiconductor element.

As described above, in the semiconductor element 1 according to the present invention, the p-side ohmic electrode 6 is not formed in the opening 6d, and the p-type contact layer 7 is exposed in this portion, whereby the p-side ohmic electrode 6 and p The contact area with the mold contact layer 7 is reduced. This can reduce the influence of migration of the p-side ohmic electrode material that occurs during energization. Further, the heat in the process of bonding the conductive substrate 2 through the conductive adhesive layer 3 or the laser beam irradiated when the growth substrate 21 is peeled off passes through the growth substrate 21 and the semiconductor layers 7 to 12 and is p. The influence of the interface characteristic deterioration of the contact interface between the p-side ohmic electrode 6 and the p-type contact layer 7 caused by the heat generated by reaching the side ohmic electrode 6 can be reduced. These results, considered according to this preferred embodiment that can suppress an increase in the operating voltage of the semiconductor element 1 as.

  Further, by covering the p-side ohmic electrode 6 with the insulating film 5 having low thermal conductivity, the heat conducted from the conductive adhesive layer 3 to the p-side ohmic electrode 6 is suppressed when the conductive substrate 2 is bonded. Therefore, deterioration of the contact interface between the p-side ohmic electrode 6 and the p-type contact layer 7 can be further suppressed.

(Second Embodiment)
Next, a semiconductor element (LED element) according to the second embodiment in which a reflective film is provided between the p-side ohmic electrode and the conductive adhesive layer will be described with reference to the drawings. FIG. 12 is a view showing a cross-sectional structure of a semiconductor device according to the second embodiment. In addition, about the structure similar to 1st reference form, the same code | symbol is attached | subjected and description is abbreviate | omitted.

As shown in FIG. 12, the semiconductor element 1 </ b> A according to the second embodiment further includes a reflective film 31 and an insulating film 32 compared to the first reference embodiment.

The reflective film 31 is formed between the insulating film 5 and the insulating film 32 so as to cover the entire surface of the insulating film 5 except for the region where the p-side connection electrode 4 and the insulating film 32 are formed. The reflective film 31 is made of an Ag film having a thickness of about 200 nm. In addition, as a material of the reflective film 31, another material with high reflectance can be applied, and for example, Al and Rh, or an alloy containing Ag, Al, and Rh can be applied. The insulating film 32 is for insulating the reflective film 31 from the p-side connection electrode 4, the conductive adhesive layer 3, and the p-side ohmic electrode 6. The insulating film 32 is made of, for example, a SiO ₂ film having a thickness of about 400 nm, and an electrode opening 32 a is formed at a position corresponding to the p-side connection electrode 4.

  Next, a method for manufacturing the semiconductor device according to the second embodiment will be described with reference to the drawings. 13 and 14 are cross-sectional views in each manufacturing process of the semiconductor element.

First, as shown in FIG. 13, the buffer layer 22 to the insulating film 5 are sequentially formed on the growth substrate 21 by the same process as in the first reference embodiment. Thereafter, the reflective film 31 is formed on the insulating film 5 by using an electron beam vapor deposition method and a lithography technique.

Next, as shown in FIG. 14, after an SiO ₂ film is formed by electron beam evaporation or sputtering, the electrode opening 32a is patterned by using a lithography technique to form an insulating film 32.

After that, the p-side connection electrode 4 is formed by the same process as in the first reference embodiment, the conductive substrate 2 is adhered, and then the element isolation is performed to complete the semiconductor element 1A.

Next, experimental results measured for the operating voltage characteristics and the light output characteristics of the semiconductor element 1A according to the second embodiment will be described. In the present experiment were compared with the semiconductor device 1A of the second embodiment, the semiconductor device for comparison in the first referential embodiment of the semiconductor device 1 and above the first reference embodiment.

First, the experimental result of the operating voltage characteristic will be described. The operating voltage of the semiconductor device 1A according to the second embodiment when a current of about 20 mA was passed was about 3.63V. This is substantially the same as the operating voltage (about 3.65 V) of the first reference form at 20 mA described above, and is found to be lower than the operating voltage (about 3.83 V) of the semiconductor element for comparison. Thus, it can be seen that also in the semiconductor element 1A according to the second embodiment, an increase in the operating voltage of the semiconductor element 1 can be suppressed as in the semiconductor element 1 of the first reference embodiment.

Next, the experimental results of the light output characteristics will be described. When a current of about 20 mA is passed, the light output of the semiconductor element 1A according to the second embodiment is about 3.5 mW, whereas the first reference embodiment The light output of the semiconductor device 1 was about 2.5 mW, and the light output of the comparative semiconductor device was about 2.8 mW. As a result, it is understood that the semiconductor element 1A according to the second embodiment can increase the light output by forming the reflective film 31 insulated by the insulating films 5 and 32.

This is because, in the semiconductor element 1 according to the first reference embodiment, light is reflected by the p-side ohmic electrode 6, but the light output is reduced because the p-side ohmic electrode 6 is formed with an opening 6d and less light is reflected. It is thought that. In the comparative semiconductor element, light is reflected by the p-side ohmic electrode formed over the entire surface of the p-side contact layer. However, since a current flows through the p-side ohmic electrode, the p-side ohmic electrode is energized. Deteriorated under the influence of migration that occurs. In addition, since the p-side ohmic electrode of the comparative semiconductor element is formed over the entire surface of the p-type contact layer, a large amount of heat is conducted when the conductive substrate is bonded. to degrade. For this reason, it is considered that the reflectance by the p-side ohmic electrode was lowered and the light output was lowered.

  On the other hand, in the semiconductor element 1A according to the second embodiment, the reflective film 31 is formed of Ag which has high reflectivity but is easily affected by migration caused by energization. However, the reflective films 31 are insulated by the insulating films 5 and 32. Thus, deterioration due to migration caused by energization can be prevented. Further, by forming an insulating film 32 having low thermal conductivity between the reflective film 31 and the conductive adhesive layer 3, heat conducted to the reflective film 31 when the heated conductive adhesive layer 3 is bonded. Therefore, deterioration of the reflective film 31 can be suppressed. As a result, the reflectance of the reflective film 31 can be maintained, and it is considered that the light output has been improved.

As described above, since the semiconductor element 1A according to the second embodiment includes the p-side ohmic electrode 6 partially formed on the p-type contact layer 7, the same effect as that of the semiconductor element 1 according to the first reference embodiment. By providing the reflective film 31 insulated by the insulating films 5 and 32, it is possible to prevent migration caused by energization and deterioration of the reflective film 31 due to heat, so that the reflectance can be maintained. The light output can be improved.

  Further, by providing the reflective film 31 separately from the p-side ohmic electrode 6, the p-side ohmic electrode 6 does not need to be composed of Ag or the like that has high reflectivity but is easily affected by migration caused by energization. The ohmic electrode 6 can be made of a metal material that is not easily affected by migration caused by energization. As a result, deterioration of the p-side ohmic electrode 6 can be further suppressed, and when the p-side ohmic electrode is made of a metal such as Ag that is susceptible to migration caused by energization, dendritic Ag is formed in the semiconductor layer. And the like can be prevented, so that a short circuit between the p-type semiconductor layer and the n-type semiconductor layer can be suppressed.

As mentioned above, although this invention was demonstrated in detail using the said embodiment and reference form , it is clear that this invention is not limited to embodiment described in this specification. The present invention can be implemented with modifications within the spirit and scope of the present invention defined by the description of the scope of claims. That is, the description of the present specification is an example, and the present invention is not construed as being limited in any way. Hereinafter, modified embodiments in which the above-described embodiment is partially modified will be described.

(First modification)
For example, in the first reference embodiment described above, the insulating film 5 may be configured to function as a reflective film. In such a configuration, it is desirable that 90% or more of the light emitted by the active layer 10 can be reflected by the insulating film 5. For example, when the wavelength of light emitted from the active layer 10 is 405 nm, 5 pairs of a 69.8 nm SiO ₂ film and a 42.9 nm TiO ₂ film are stacked from the p-type contact layer 7 side. A dielectric multilayer film can be applied as the reflective insulating film 5. The dielectric multilayer film may be composed of other dielectric layers such as Al ₂ O ₃ and ZrO _2, or the number of pairs to be stacked may be changed.

In the first reference embodiment, since the light incident on the opening 6d of the p-side ohmic electrode 6 is not reflected, the light output is reduced. In this way, by configuring the insulating film 5 with a reflective dielectric multilayer film, Since the light incident on the opening 6d of the p-side ohmic electrode 6 can be reflected by the insulating film 5 made of a dielectric multilayer film, the light output can be improved. Further, since the insulating film 5 is not affected by migration caused by energization, it is possible to prevent the reflectance of the insulating film 5 from being lowered. Further, by providing the insulating film 5 with a reflection function, the configuration can be simplified and downsized as compared with the case where a separate reflection film is provided.

(Second modification)
In the second embodiment described above, the p-side ohmic electrode 6 may be configured to transmit most of the light emitted by the active layer. For example, by forming the p-side ohmic electrode 6 from the p-type contact layer 7 side by a Pd layer having a thickness of about 2 nm, an Au layer having a thickness of about 4 nm, and a Ti layer having a thickness of about 1 nm, light of about 50% Can be transmitted. The p-side ohmic electrode 6 is selected from a group that can form an ohmic contact and can transmit light, for example, Pd, Pt, Au, Ni, Rh, Ti, Al, Si. Moreover, you may comprise with at least 1 sort (s) of material.

  By comprising in this way, the light absorbed by the p side ohmic electrode 6 can be reduced, and much light can be permeate | transmitted. As a result, more light can reach the reflecting film 31 and be reflected, so that the light output can be further improved.

(Other changes)
Moreover, although the example which applied this invention to the light emitting diode was shown in the above-mentioned 1st reference form, you may apply this invention to semiconductor elements, such as semiconductor light emitting elements other than a light emitting diode, and a semiconductor light receiving element.

It is sectional drawing of the semiconductor element by a 1st reference form. It is a top view along the II-II line of FIG. It is sectional drawing in each manufacturing process of a semiconductor element. It is sectional drawing in each manufacturing process of a semiconductor element. It is sectional drawing in each manufacturing process of a semiconductor element. It is sectional drawing in each manufacturing process of a semiconductor element. It is sectional drawing in each manufacturing process of a semiconductor element. It is sectional drawing in each manufacturing process of a semiconductor element. It is sectional drawing in each manufacturing process of a semiconductor element. It is sectional drawing in each manufacturing process of a semiconductor element. It is a figure which shows the operating voltage of this invention and the sample for a comparison. It is a figure which shows the cross-section of the semiconductor element by 2nd Embodiment. It is sectional drawing in each manufacturing process of a semiconductor element. It is sectional drawing in each manufacturing process of a semiconductor element.

DESCRIPTION OF SYMBOLS 1, 1A Semiconductor element 2 Conductive substrate 3 Conductive adhesive layer 4 P side connection electrode 5 Insulating film 6 P side ohmic electrode 6a Stripe part 6b Connection part 6c Connection part 6d Opening part 7 P-type contact layer 8 P-type cladding layer 9 p-type cap layer 10 active layer 11 n-type cladding layer 12 n-type contact layer 31 reflective film 32 insulating film

Claims (2)

A semiconductor layer comprising an active layer comprising a nitride-based semiconductor;
A conductive substrate to which the semiconductor layer is bonded via a conductive adhesive layer;
An ohmic electrode provided on one surface of the semiconductor layer facing the conductive substrate;
A first insulating film provided between the ohmic electrode and the conductive adhesive layer and covering the ohmic electrode;
A connection electrode for penetrating the first insulating film and electrically connecting the ohmic electrode and the conductive substrate;
The ohmic electrode has a plurality of stripe portions to which the connection electrodes are not connected, a connecting portion for connecting the plurality of stripe portions, and a connection portion to which the connection electrodes are connected, and the plurality of stripe portions An opening is formed in between, a part of one surface of the semiconductor layer is exposed from the opening ,
The first insulating film is provided to cover one surface of the semiconductor layer exposed from the ohmic electrode,
A reflective film insulated from the ohmic electrode by the first insulating film is provided between the ohmic electrode and the conductive adhesive layer;
A second insulating film that insulates the reflective film from the conductive adhesive layer and the connection electrode is formed between the reflective film and the conductive adhesive layer.
The reflective film is formed so as to cover the entire surface of the first insulating film other than the region where the connection electrode and the second insulating film are formed.
The light emitted from the active layer is extracted to the outside from the surface of the semiconductor layer opposite to the surface facing the reflective film. The reflective film according to claim 1 Symbol mounting the semiconductor device characterized by comprising the Ag film.

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