JP2014175338A - Semiconductor light-emitting element and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting element and a manufacturing method of the same, which can uniform a distribution of an emission intensity in a light emitting plane without decreasing manufacturing yield.SOLUTION: A semiconductor light-emitting element has a structure where a cap electrode 11, a repeller 12, a p-electrode film 13, a p-GaN (gallium nitride) layer 14, a luminescent layer 15, an n-GaN layer 16 and an n-electrode 17 are laminated on a support substrate 10. A structure in which the p-GaN layer, the luminescent layer and the n-GaN layer are laminated becomes an LED layer 19. In the p-electrode film among the p-electrode film and the n-electrode film which sandwich the LED layer in which the p-GaN (gallium nitride) layer, the luminescent layer and the n-GaN layer are laminated, low-resistance regions LR and high-resistance regions HR in which the high-resistance region and the low-resistance region have resistance values different from each other are alternately formed one by one along a boundary surface between the LED layer and the p-electrode film. In the p-electrode film, the high-resistance regions and the low-resistance regions are formed at positions where a current path between the high-resistance region and the n-electrode across the LED layer is shorter than a current path between the low-resistance region and the n-electrode across the LED layer.

Description

  The present invention relates to a semiconductor light emitting element such as a light emitting diode (LED) and a method for manufacturing the same.

  In recent years, nitride-based semiconductor light-emitting devices having a structure in which an active layer (also referred to as a light-emitting layer) is sandwiched between a p-type nitride semiconductor layer and an n-type nitride semiconductor layer are known. Yes. In such a semiconductor light emitting device, a conductive electrode film formed so as to cover the entire surface of the p-type nitride semiconductor layer and a part of the surface of the n-type nitride semiconductor layer are formed. Light is emitted from the active layer by applying a voltage between the electrode pieces, and the light is extracted to the outside through the n-type nitride semiconductor layer. Here, the electrode piece formed on the surface of the n-type nitride semiconductor layer is preferably formed to be smaller than the surface of the n-type nitride semiconductor layer in order to suppress a decrease in light extraction efficiency. . According to such a configuration, the resistance value of the region facing the electrode piece in the n-type nitride semiconductor layer in the active layer and the region sandwiched between the electrode pieces are lower than those of the other regions. Thus, the drive current flows intensively. Thereby, the problem that luminous efficiency worsens has arisen.

  To solve this problem, a nitride semiconductor light emitting device is proposed in which only the region facing the electrode piece on the surface of the p-type nitride semiconductor layer has a higher resistance than other regions. (For example, see Patent Document 1). In such a nitride semiconductor light emitting device, after forming a p-type nitride semiconductor layer, the region facing the electrode piece on the surface thereof is subjected to plasma treatment using an inert gas, thereby making the region highly resistive. It tries to become.

JP 2007-180504 A

  By the way, in order to perform the plasma treatment only on the region facing the electrode piece on the surface of the p-type nitride semiconductor layer, the resist is patterned in other regions other than the region, and then the resist is removed and washed. The power surface treatment is applied to the p-type nitride semiconductor layer. At this time, if the surface state of the p-type nitride semiconductor layer deteriorates due to such surface treatment, an electrode film cannot be satisfactorily formed on the surface of the p-type nitride semiconductor layer in the subsequent process, and the yield decreases. There was a risk of inviting.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a semiconductor light emitting element capable of improving the light emission efficiency without reducing the yield and a method for manufacturing the same.

  A semiconductor light emitting device according to the present invention includes a first conductive type first semiconductor layer, a light emitting layer, and an LED layer in which a second conductive type second semiconductor layer opposite to the first conductive type is stacked. A first electrode formed on the first semiconductor layer, and a second electrode formed on the second semiconductor layer, wherein the first electrode includes the LED layer and the A low resistance region and a high resistance region having different resistance values are formed along an interface with the first electrode, and the high resistance region and the second electrode through the LED layer are formed in the first electrode. The high resistance region and the low resistance region are formed at positions where the current path between them is shorter than the current path between the low resistance region and the second electrode via the LED layer.

  The method of manufacturing a semiconductor light emitting device according to the present invention includes a first conductive type first semiconductor layer, a light emitting layer, and a second conductive type second semiconductor layer opposite to the first conductive type. An LED layer forming step for forming a laminated LED layer, a first electrode forming step for forming a first electrode on the first semiconductor layer, and a second electrode for forming a second electrode on the second semiconductor layer. Forming a patterned resist on the two-electrode formation step and the first electrode, and applying oxygen plasma treatment to the first electrode using the resist as a mask, a part of the first electrode is made highly resistive A high resistance step of alternately forming a high resistance region and a low resistance region having a resistance value lower than that of the high resistance region along an interface between the LED layer and the first electrode, and In the second electrode forming step, the high-resistance region through the LED layer And the second electrode at a position on the second semiconductor layer such that the current path between the second electrodes is shorter than the current path between the low resistance region and the second electrode through the LED layer. Form.

  As described above, in the semiconductor light emitting device according to the present invention, the first conductivity type first semiconductor layer, the light emitting layer, and the second conductivity type second semiconductor layer opposite to the first conductivity type are stacked. The first electrode of the first and second electrodes sandwiching the LED layer alternately has a low resistance region LR and a high resistance region HR having different resistance values along the interface between the LED layer and the first electrode. Is formed. At this time, in the first electrode, the current path between the high resistance region and the second electrode through the LED layer is shorter than the current path between the low resistance region and the second electrode through the LED layer. The high resistance region and the low resistance region are respectively formed.

  According to such a configuration, it is possible to prevent the current from being concentrated only in the high resistance region where the current path between the first electrode and the second electrode is short via the LED layer. Thereby, luminous efficiency is improved.

  Further, in the semiconductor light emitting device according to the present invention, in order to achieve the object of diffusing the drive current flowing in the LED layer, a part of the region (HR) of the first electrode is increased in resistance. Therefore, a problem that occurs when a part of the semiconductor layer in the LED layer is increased in resistance by plasma treatment in order to achieve such an object is avoided. That is, according to the semiconductor light emitting device according to the present invention, the resist removal process is not performed on the surface of the semiconductor layer when the semiconductor layer is subjected to plasma processing. Therefore, the problem that the surface of the semiconductor layer is deteriorated to such a state that the electrode film cannot be satisfactorily formed due to the resist removal treatment is avoided.

  Therefore, according to the semiconductor light emitting element according to the present invention, it is possible to improve the light emission efficiency without reducing the yield.

It is sectional drawing of the semiconductor light-emitting device 100 which is Example 1 of this invention. It is a flowchart which shows the manufacture procedure of a semiconductor light-emitting device. It is a manufacturing process figure which shows the cross section of element structure for every manufacturing process. It is a manufacturing process figure which shows the cross section of element structure for every manufacturing process. It is a figure which shows the electric current path | route in a LED layer. 4 is a cross-sectional view of a semiconductor light emitting device in which a p electrode film 13 is patterned in a region other than a region facing an n electrode 17 on a p-GaN layer 14. FIG. FIG. 6 is a manufacturing process diagram when patterning a p-electrode film 13 on a p-GaN layer 14. It is sectional drawing of the semiconductor light-emitting device 200 which is Example 2 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a cross section of a semiconductor light emitting device 100 according to a first embodiment of the present invention. As shown in FIG. 1, such a semiconductor light emitting device has a cap electrode 11, a reflective electrode 12, a p electrode film 13, a p-GaN (gallium nitride) layer 14, a light emitting layer 15, and an n-GaN layer on a support substrate 10. 16 and an n-electrode 17 are stacked. At this time, the structure in which the p-GaN layer 14, the light emitting layer 15, and the n-GaN layer 16 are stacked serves as the LED layer 19.

  The support substrate 10 is made of, for example, Si (silicon) having a thermal conductivity of 60 W / mK or 150 W / mK. The support substrate 10 may be CuW (copper tungsten) having a thermal conductivity of 160 W / mK, AlN (aluminum nitride) having a thermal conductivity of 17 W / mK, SiC (silicon carbide) having a thermal conductivity of 300 W / mK, or thermal conductivity. Cu (copper) or the like having a rate of 400 W / mK may be used.

  The cap electrode 11 is formed on the support substrate 10, and a metal such as Ti (titanium) / Pt (platinum) / Au (gold) or TiW (titanium tungsten) / Ti / Pt / Au is laminated thereon. The electrode film having a thickness of about 500 μm or more.

  The reflective electrode 12 is formed on the cap electrode 11 and is an electrode film made of, for example, Ag (silver) with a film thickness of about 40 nm or more. The reflective electrode 12 is provided to reflect the light emitted from the light emitting layer 15. At this time, in order to obtain a high reflectance, the thickness of the reflective electrode 12 is desirably 50 nm or more.

  The p-electrode film 13 is formed between the reflective electrode 12 and the p-GaN layer 14, and is made of, for example, ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide), and has a thickness of about 5 nm to 50 nm. It is a transparent conductive metal oxide film. The p electrode film 13 includes a low resistance region LR having a resistance value of ITO or IZO itself, which is a material of the p electrode film 13, and a high resistance region HR having a resistance value higher than that of the low resistance region LR. As shown in FIG. 4, the LED layer 19 is formed along the interface between the p-electrode film 13 and the p-electrode film 13. At this time, the high resistance region HR and the low resistance region LR are formed in the p electrode film 13 such that the distance between the high resistance region HR and the n electrode 17 through the LED layer 19 is low through the LED layer 19. Each is formed at a position smaller than the distance between the LR and the n-electrode 17. The high resistance region HR has a higher oxygen concentration than the low resistance region LR, and thus has a higher resistance value than the low resistance region LR.

The p-GaN layer 14 is formed on the p-electrode film 13. For example, p-type GaN having a thickness of about 0.05 μm to 0.03 μm to which a p-type dopant such as Mg (magnesium) is added. This is a semiconductor layer made of a system semiconductor crystal film. The light emitting layer 15 includes alternating well layers made of InGaN (indium gallium nitride) crystals and barrier layers made of In _x Ga _(1-x) N crystals or GaN crystals having an In composition (X) smaller than the well layers. In other words, it has a so-called multiple quantum well (MQW) structure that is laminated repeatedly. The thickness of each of the well layer and the barrier layer is about 3 nm to 10 nm. The n-GaN layer 16 is formed on the light emitting layer 15 and is made of an n-type GaN-based semiconductor crystal film having a film thickness of about 3 μm to 7 μm to which an n-type dopant such as Si (silicon) is added. A semiconductor layer. Note that the surface of the n-GaN layer 16 facing the interface with the light emitting layer 14 is a light extraction surface for extracting light emitted from the light emitting layer 15 to the outside.

  The structure in which the p-GaN layer 14, the light emitting layer 15, and the n-GaN layer 16 are stacked serves as an LED layer 19 as a light emitting diode.

  The n electrode 17 is formed by laminating a metal such as Ti / Al / Pt / Au or Ti / Ni / Au formed so as to cover the surface of the n-GaN layer 16, that is, a part of the light extraction surface. It is an electrode piece. As shown in FIG. 1, the n electrode 17 is formed on the n-GaN layer 16 at a position facing the high resistance region HR of the p electrode film 13.

  FIG. 2 is a flowchart showing a manufacturing procedure when manufacturing the semiconductor light emitting device described above. First, as shown in FIG. 3A, by the metal organic chemical vapor deposition (hereinafter referred to as MOCVD) method, on the growth substrate 9 made of sapphire or the like, the above-described n-GaN layer 16, light emitting layer 15 and p. The LED layer in which the GaN layer 14 is sequentially stacked is formed (LED layer forming step S1).

  Next, by sputtering or EB (electron beam) deposition, as shown in FIG. 3B, a transparent conductive metal oxide such as ITO or IZO having a film thickness of about 5 nm to 30 nm is formed on the p-GaN layer 14. A p-electrode film 13 made of a film is formed (p-electrode forming step S2).

  Next, as shown in FIG. 3C, a resist Rg is patterned at a location where the low resistance region LR is to be formed on the p-electrode film 13, and subsequently, as shown in FIG. The oxygen plasma treatment is performed on the p-electrode film 13 at a pressure of 1.0 Pa and a treatment time of 1 minute.

  According to such oxygen plasma treatment, a region of the p-electrode film 13 that is not covered with the resist Rg is exposed to oxygen plasma, and oxygen is taken into the region. As a result, the oxygen concentration in the region not covered with the resist Rg in the p-electrode film 13 is increased, and the resistance is increased. Thereafter, as shown in FIG. 3E, the transmittance of the p-electrode film 13 is increased by oxidizing the surface of the p-electrode film 13 with the resist Rg removed. For example, the surface of the p electrode film 13 is annealed for 1 minute to 10 minutes at a treatment temperature of 400 ° C. to 600 ° C. in an oxygen atmosphere using, for example, an RTA (rapid heating) apparatus, The oxygen concentration on the surface of the p electrode film 13 is increased.

According to such oxidation treatment, oxygen atoms are taken into the crystal lattice in the region of the p-electrode film 13 exposed to oxygen plasma, and the resistance value of this region is further increased. Therefore, by the above-described oxygen plasma treatment and oxidation treatment, the low resistance region LR of the resistance value (for example, ITO contact resistance of 10 ⁻⁴ ohm) of the material used as the p-electrode film 13 and the resistance value of about 5-30. As shown in FIG. 3E, high resistance regions HR having a resistance value of about twice are alternately formed along the interface between the LED layer 19 and the p electrode film 13 (high resistance step S3).

  After execution of the oxidation treatment shown in FIG. 3 (e), as shown in FIG. 4 (a), the p-electrode film 13 is patterned into a form for each element, and subsequently on the p-electrode film 13 by sputtering or EB vapor deposition. Then, the reflective electrode 12 made of Ag and having a thickness of about 50 nm or more is formed (reflective electrode forming step S4).

  Next, as shown in FIG. 4A, a cap electrode 11 having a film thickness of about 500 μm or more formed by laminating a metal such as Ti / Pt / Au on the reflective electrode 12 by sputtering or EB deposition. (Cap electrode forming step S5). At this time, one interface of the cap electrode 11, that is, the bonding surface with the reflective electrode 12, is formed of Ti, and the other interface, that is, the bonding surface with the support substrate 10 is formed of Au. In order to prevent migration of the reflective electrode 12, that is, Ag (silver), the material of the cap electrode 11 is an alloy containing a barrier metal such as TiW (titanium tungsten), for example, TiW (titanium tungsten) / It is desirable to use an alloy in which Ti / Pt / Au is laminated.

  Next, the LED layer 19 is divided into elements by performing a dry etching process, and subsequently, the support substrate 10 is bonded to the divided cap electrode 11 as shown in FIG. 4B (support substrate bonding). Step S6). An Au (gold) film (not shown) is formed on the surface of the support substrate 10, and in the support substrate bonding step S6, the surface of the cap electrode 11 and the surface of the support substrate 10 are bonded by Au / Au bonding. Bonding by wafer bonding. In addition, as a method of bonding the support substrate 10 to the cap electrode 11, not only the above-described metal-to-metal bonding but also metal eutectic bonding may be used. At this time, for example, Sn (tin) is formed on the surface of the support substrate 10 instead of Au (gold), and the surface of the support substrate 10 and the cap electrode 11 are bonded (Sn / Au bonding).

  3 (a) to 3 (e) and 4 (a) show a partial cross-sectional structure in the wafer. FIG. 4 (b) and FIGS. (D) shows a cross-sectional structure of one light emitting element divided from the wafer.

  After completion of the support substrate bonding step S6 described above, the growth substrate 9 is removed from the n-GaN layer 16 and removed by the laser lift-off method as shown in FIG. 4C (growth substrate removal step S7). .

  Next, an electrode film such as Ti / Al / Pt / Au or Ti / Ni / Au is formed on the n-GaN layer 16 at a position facing the high resistance region HR by sputtering or EB deposition. The n electrode 17 is formed as shown in FIG. That is, the n-GaN layer in which the current path between the high resistance region HR and the n electrode 17 via the LED layer 19 is shorter than the current path between the low resistance region LR and the n electrode 17 via the LED layer 19. The n electrode 17 is formed at a position on the surface 16 (n electrode forming step S8).

  The high resistance region HR has a size larger than that of the n electrode 17 when viewed from above the n-GaN layer 16 in a plan view, and the n electrode 17 fits in the high resistance region HR. It is preferable to form at a position.

  As described above, in the semiconductor light emitting device 100 shown in FIG. 1, the p-electrode film 13 covering the surface of the p-GaN layer 14 has a resistance value along the interface between the LED layer 19 and the p-electrode film 13. An electrode film in which different low resistance regions LR and high resistance regions HR are alternately formed is adopted. At this time, the high resistance region HR of the p electrode film 13 is formed at a position facing the n electrode 17 covering a part of the surface of the n-GaN layer 16. That is, as shown in FIG. 5, in the p-electrode film 13, the current path L <b> 2 between the high-resistance region HR and the n-electrode 17 via the LED layer 19 corresponds to the low-resistance region LR and n-electrode via the LED layer 19. The high resistance region HR and the low resistance region LR are respectively formed at positions that are shorter than the current path L <b> 1 between 17.

  According to such a configuration, a drive current flows from the low resistance region LR of the p electrode film 13 to the n electrode 17 side through the current path L1 (shown by a one-dot chain line) in the LED layer 19. In addition, a drive current flows from the high resistance region HR of the p electrode film 13 to the n electrode 17 side through the current path L2 in the LED layer. At this time, as shown in FIG. 5, the high resistance region HR of the p electrode film 13 exists at a position facing the n electrode 17 across the LED layer, and the low resistance region LR of the p electrode film 13 extends to the n electrode 17. Since it exists in the position which shifted | deviated from the opposing position, the path length of the current path L2 becomes shorter than the path length of the current path L1. That is, the resistance value in the current path L2 formed between the high resistance region HR of the p electrode film 13 and the n electrode 17 is the current path L1 formed between the low resistance region LR of the p electrode film 13 and the n electrode 17. It becomes lower than the resistance value at. However, since the high resistance region HR in the p-electrode film 13 has a higher resistance value than the low resistance region LR, it is possible to prevent a large amount of current from concentrating on the current path L2 and to spread the current also in the current path L1. It becomes possible.

  Therefore, according to the semiconductor light emitting device 100 shown in FIG. 1, it becomes possible to flow a driving current over a wide range of the LED layer 19 and to improve the light emission efficiency.

  At this time, the difference between the current values flowing in the current path L1 and the current path L2 can be reduced by the resistance value, but the current value flowing in the current path L1 can be made larger than the current path L2. Even in such a case, the effect of spreading the current over a wide range is exhibited in the same manner, which leads to an improvement in luminous efficiency. In addition, when an electrode that does not transmit light is present on the light emitting surface as shown in FIG. 1, light emission directly under the electrode is inhibited by the electrode, and light cannot be extracted. Therefore, more efficient light emission can be realized when a larger amount of current flows through the current path L1 that is off from directly below the electrode.

  In the semiconductor light emitting device 100 shown in FIG. 1, as described above, the drive current flowing in the LED layer is made uniform by increasing the resistance of a partial region (HR) of the p electrode film 13. I have to. This avoids the following problems that occur when a part of the GaN-based semiconductor layer included in the LED layer is increased in resistance by plasma treatment in order to widen the drive current flowing in the LED layer. That is, conventionally, in order to increase the resistance of a part of the GaN-based semiconductor layer, resist patterning, plasma treatment using an inert gas, and resist removal processing are performed on the GaN-based semiconductor layer. become. However, in the resist removal process, the surface condition of the GaN-based semiconductor layer is deteriorated by the resist remover and the cleaning agent applied to the surface of the GaN-based semiconductor layer, that is, an electrode film can be formed on the surface in the subsequent process. In some cases, the surface condition deteriorated so that it could not be obtained.

  At this time, in the semiconductor light emitting device 100 shown in FIG. 1, the surface of the GaN-based semiconductor layer (14) is not subjected to a resist removal treatment that deteriorates the surface state. In addition, it is possible to form the electrode film satisfactorily.

  Therefore, according to the semiconductor light emitting device of the present invention, it is possible to make the light emission intensity distribution uniform within the light emitting surface without reducing the yield.

  In the present invention, in order to achieve the purpose of diffusing the drive current flowing in the LED layer, the p electrode film 13 having a high resistance region HR and a low resistance region LR is employed. However, in order to achieve the same purpose, it is conceivable to pattern the p-electrode film 13 in a region other than the region facing the n-electrode 17 on the p-GaN layer 14 as shown in FIG. At this time, in order to pattern the p-electrode film 13 on the p-GaN layer 14, after the series of steps shown in FIGS. 3A to 3C is completed, as shown in FIG. The p electrode film 13 is etched. By this etching process, a portion of the p-electrode film 13 that is not covered with the resist Rg is removed. However, the removal may not be performed completely. At this time, an electrode residue PZ as shown in FIG. 7B remains on the p-GaN layer 14. Next, a resist removing process for removing the resist Rg as shown in FIG. 7B is performed using a resist remover and a cleaning agent. However, the removal may not be completed completely. At this time, a resist residue EZ as shown in FIG. 7C remains on the p-electrode film 13. Thereafter, as shown in FIG. 7C, the reflective electrode 12 made of Ag (silver) is formed on the p electrode film 13 and the p-GaN layer 14. However, since the surface state of the p-GaN layer 14 is deteriorated by the etching solution used in the above etching process and the resist remover and cleaning agent used in the resist removal process, the p-GaN layer 14 and the reflective electrode are deteriorated. Ag (silver) aggregation GS as shown in FIG. 7C may occur at the 12 interfaces.

  Accordingly, when a structure in which the p-electrode film 13 is patterned as shown in FIG. 6 is adopted, the electrode residue PZ remaining in the reflective electrode 12 and the p-GaN as shown in FIG. There is a problem that the reflectivity at the reflective electrode 12 is lowered due to Ag aggregated GS generated at the interface between the layer 14 and the reflective electrode 12.

  However, in the semiconductor light emitting device according to the present invention, the etching process is not performed on the p-electrode film 13, and therefore there is no possibility that the residue of the electrode residue PZ and the aggregation GS of Ag occur. Therefore, according to the present invention, since the reflectance of the reflective electrode 12 is not reduced due to the aggregate GS of the electrode residues PZ and Ag, highly efficient light emission can be realized.

In the above-described embodiment, the semiconductor light emitting device has been described by taking the thin film film structure as shown in FIG. 1 as an example, but it can also be applied to a flip chip structure device.
FIG. 8 is a cross-sectional view showing the configuration of the semiconductor light emitting device 200 according to the second embodiment of the present invention having a flip-chip structure made in view of the above point.

  The semiconductor light emitting device 200 shown in FIG. 8 has a structure in which a cap electrode 11, a reflective electrode 12, a p electrode film 13, a p-GaN layer 14, a light emitting layer 15 and an n-GaN layer 16 are stacked. 1 is the same as the semiconductor light emitting device 100 shown in FIG. However, as shown in FIG. 8, the semiconductor light emitting device 200 LED layer 19 has a recess that penetrates the p-GaN layer 14 and the light emitting layer 15 and exposes the surface of the n-GaN layer 16. One end of a columnar n-electrode 20 made of Ti / Al / Ti / Pt / Au is directly connected to the exposed surface of the n-GaN layer 16 from the recess. At this time, the other end of the n-electrode 20 is connected to a first line (not shown) wired on a substrate 50 made of, for example, PCB (printed circuit board) via a bonding metal 21A. The electrode 11 is connected to a second line (not shown) wired on the substrate 50 via a bonding metal 21B. In the p electrode film 13 formed in the semiconductor light emitting device 200, the region closest to the n electrode 20 is the above-described high resistance region HR, and the region away from one end of the n electrode 20 is low resistance. This is a region LR. That is, as in the case of FIG. 5, the current path in the LED layer 19 becomes longer and the resistance value thereof becomes higher in the region far from the n-electrode 20 in the p-electrode film 13. In this case, by increasing the resistance of the region that is closest to the n-electrode 20, the drive current flowing in the LED layer is diffused. In the example shown in FIG. 8, the growth substrate 9 for forming the LED layer remains attached to the LED layer, but it may be peeled off.

  In short, the semiconductor light emitting device according to the present invention includes an LED layer 19 in which a p-GaN layer 14 as a first semiconductor layer, a light emitting layer 15 and an n-GaN layer 16 as a second semiconductor layer are stacked, A p-electrode film 13 as a first electrode formed on the first semiconductor layer and an n-electrode 17 (20) as a second electrode formed on the second semiconductor layer are included. Here, in the first electrode, a low resistance region (LR) and a high resistance region (HR) having different resistance values are formed along the interface between the LED layer and the first electrode. At this time, in the high resistance region and the low resistance region, the current path between the high resistance region and the second electrode through the LED layer is shorter than the current path between the low resistance region and the second electrode through the LED layer. It is formed at each position.

  Although the first semiconductor layer is described as a p-type semiconductor layer and the second semiconductor layer is described as an n-type semiconductor layer, the first semiconductor layer is an n-type semiconductor layer, and the second semiconductor layer is It may be a p-type semiconductor layer. In short, the LED layer has a structure in which a first conductivity type first semiconductor layer, a light emitting layer, and a second conductivity type second semiconductor layer opposite to the first conductivity type are stacked. If it is good.

DESCRIPTION OF SYMBOLS 12 Reflective electrode 13 p electrode film 14 p-GaN layer 15 Light emitting layer 16 n-GaN layer 17 n electrode 100, 200 Semiconductor light emitting element

Claims (6)

An LED layer in which a first semiconductor layer of a first conductivity type, a light emitting layer, and a second semiconductor layer of a second conductivity type opposite to the first conductivity type are stacked, and the first semiconductor layer A first electrode formed on the second semiconductor layer, and a second electrode formed on the second semiconductor layer,
A low resistance region and a high resistance region having different resistance values are formed along the interface between the LED layer and the first electrode in the first electrode.
In the first electrode, a current path between the high resistance region and the second electrode via the LED layer is shorter than a current path between the low resistance region and the second electrode via the LED layer. The semiconductor light emitting element, wherein the high resistance region and the low resistance region are formed at positions. 2. The semiconductor light emitting element according to claim 1, wherein the second electrode is formed at a position facing the high resistance region on the second semiconductor layer. The LED layer has a recess that penetrates the first semiconductor layer and the light emitting layer and exposes a surface of the second semiconductor layer;
2. The semiconductor light emitting element according to claim 1, wherein the second electrode is formed on an exposed surface of the second semiconductor layer from the recess. The said 1st electrode is a transparent conductive metal oxide film, The oxygen concentration of the said high resistance area | region is higher than the oxygen concentration of the said low resistance area | region, The any one of Claims 1-3 characterized by the above-mentioned. Semiconductor light emitting device. An LED layer forming step of forming an LED layer in which a first semiconductor layer of a first conductivity type, a light emitting layer, and a second semiconductor layer of a second conductivity type opposite to the first conductivity type are stacked;
A first electrode forming step of forming a first electrode on the first semiconductor layer;
A second electrode forming step of forming a second electrode on the second semiconductor layer;
Forming a patterned resist on the first electrode, and subjecting the first electrode to an oxygen plasma treatment using the resist as a mask; A high resistance step of alternately forming a low resistance region having a resistance value lower than that of the high resistance region along the interface between the LED layer and the first electrode,
In the second electrode forming step, the current path between the high resistance region and the second electrode via the LED layer is more than the current path between the low resistance region and the second electrode via the LED layer. A method of manufacturing a semiconductor light emitting element, wherein the second electrode is formed at a position on the second semiconductor layer so as to be shortened. 6. The method of manufacturing a semiconductor light emitting element according to claim 5, wherein, in the step of increasing resistance, after the oxygen plasma treatment, an oxidation treatment is performed on the surface of the second electrode in a state where the resist is removed.

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