JP5849388B2 - Semiconductor light emitting device - Google Patents

Description

  The present invention relates to a semiconductor light emitting device having a structure in which an n-type semiconductor layer, an active layer, and a p-type semiconductor layer are stacked.

  In a semiconductor light-emitting device having a structure in which an n-type semiconductor layer, an active layer, and a p-type semiconductor layer are stacked, such as a light-emitting diode (LED) or a semiconductor laser, light emission efficiency is improved. For example, a semiconductor light emitting device has been proposed in which a light-transmitting p-side electrode is formed on almost the entire surface of a p-type semiconductor layer, and a reflective film is further formed on the p-side electrode via an insulating film (for example, Patent Documents). 1). Thereby, the reflectance on the p side is improved, and the light extraction efficiency from the substrate side is improved.

Japanese Patent No. 4122785

  In the above semiconductor light emitting device, since the n-side electrode is formed over the entire exposed n-type semiconductor layer, the area of the region that does not contribute to light emission is large. For this reason, the ratio of the light emission area to the substrate area is small. Further, since the reflective layer is formed on the insulating film, there is a problem in terms of moisture resistance of the reflective layer.

  In view of the above problems, an object of the present invention is to provide a semiconductor light emitting device in which the ratio of the light emitting area to the substrate area is high and the moisture resistance of the reflective layer is improved.

According to one aspect of the present invention, (a) a stacked body in which an n-type semiconductor layer, an active layer, and a p-type semiconductor layer are stacked in this order; and (b) a transparent electrode disposed on the p-type semiconductor layer; (C) an electrode insulating film disposed on the transparent electrode; and (d) an n-side disposed on the electrode insulating film and penetrating the electrode insulating film, the transparent electrode, the p-type semiconductor layer, and the active layer. An n-side electrode in contact with the n-type semiconductor layer at the opening, and (e) a transparent electrode with a striped p-side opening provided on the electrode insulating film, spaced apart from the n-side electrode. A p-side electrode that is in contact, and (f) a reflective layer that is disposed inside the electrode insulating film or between the transparent electrode and the electrode insulating film so as to face the upper surface of the multilayer body and reflects light emitted from the active layer The n-side opening has a tapered shape whose bottom is narrower than the frontage, and below the outer edge of the n-side electrode, Active layer surrounds the side opening is disposed the transparent electrode and the reflective layer, the reflective layer has a region disposed inside the n-side opening along the slope of the tapered shape of the n-side opening The n-side electrode has a region disposed inside the n-side opening along the bottom surface from the tapered slope of the n-side opening, and is in contact with the n-type semiconductor layer at the bottom of the n-side opening, A semiconductor light emitting device is provided in which the reflective layer and the n-side electrode are made of different materials .

  ADVANTAGE OF THE INVENTION According to this invention, the ratio of the light emission area with respect to a substrate area can be high, and the semiconductor light-emitting device which improved the moisture resistance of the reflection layer can be provided.

1 is a schematic cross-sectional view showing a configuration of a semiconductor light emitting device according to a first embodiment of the present invention. 1 is a schematic plan view showing a configuration of a semiconductor light emitting device according to a first embodiment of the present invention. It is typical sectional drawing which shows the mounting method of the semiconductor light-emitting device concerning the 1st Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 1st Embodiment of this invention (the 1). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 1st Embodiment of this invention (the 2). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 1st Embodiment of this invention (the 3). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 1st Embodiment of this invention (the 4). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 1st Embodiment of this invention (the 5). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 1st Embodiment of this invention (the 6). It is typical sectional drawing which shows the other mounting method of the semiconductor light-emitting device concerning the 1st Embodiment of this invention. FIG. 6 is a schematic plan view showing another configuration of the semiconductor light emitting device according to the first embodiment of the present invention. It is typical sectional drawing which shows the structure of the semiconductor light-emitting device concerning the 2nd Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 2nd Embodiment of this invention (the 1). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 2nd Embodiment of this invention (the 2). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device which concerns on the 2nd Embodiment of this invention (the 3). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device concerning the 2nd Embodiment of this invention (the 4). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor light-emitting device concerning the 2nd Embodiment of this invention (the 5).

  First and second embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  Further, the following first and second embodiments exemplify apparatuses and methods for embodying the technical idea of the present invention, and the embodiments of the present invention include the materials of components, The shape, structure, arrangement, etc. are not specified below. The embodiment of the present invention can be variously modified within the scope of the claims.

(First embodiment)
As shown in FIG. 1, the semiconductor light emitting device 1 according to the first embodiment of the present invention includes a stacked body 20 in which an n-type semiconductor layer 21, an active layer 22, and a p-type semiconductor layer 23 are stacked in this order, The transparent electrode 30 disposed on the p-type semiconductor layer 23, the electrode insulating film 40 disposed on the transparent electrode 30, and the electrode insulating film 40, the transparent electrode 30, and the p-type semiconductor disposed on the electrode insulating film 40 An n-side electrode 51 in contact with the n-type semiconductor layer 21 through an n-side opening 41 provided through the layer 23 and the active layer 22 and a stripe provided on the electrode insulating film 40 and provided on the electrode insulating film 40 The p-side electrode 53 is in contact with the transparent electrode 30 through the p-shaped opening 43 and the reflective layer 70 is disposed inside the electrode insulating film 40 so as to face the upper surface of the stacked body 20. The reflective layer 70 reflects the light emitted from the active layer 22 to the stacked body 20 side. The n-side electrode 51 and the p-side electrode 53 are disposed on the electrode insulating film 40 so as to be separated from each other.

  Furthermore, the semiconductor light emitting device 1 shown in FIG. 1 has a structure in which a stacked body 20 is disposed on a buffer layer 11 disposed on a substrate 10. The output light L is radiated to the outside of the semiconductor light emitting device 1 from the light emitting region 110 that is a surface facing the surface in contact with the buffer layer 11 of the substrate 10.

  The substrate 10 is made of a material that transmits light generated in the active layer 22. For example, a sapphire substrate can be used as the substrate 10.

Buffer layer 11 is made of a material that transmits the light generated in the active layer 22, for _{example, Al x M y Ga 1-} xy N (M is indium (In) or boron (B), 0 <x ≦ 1,0 ≦ a first sublayer consisting of y.ltoreq.1, x + y = 1) and AlaMbGa1-a-bN (M is In or B, 0.ltoreq.a <1, 0.ltoreq.b.ltoreq.1, a + b = 1, a <x). It is possible to adopt a multilayer structure in which the second sublayers are alternately stacked. For example, the first sublayer is an aluminum nitride (AlN) film having a thickness of about 0.5 to 5 nm, and the second sublayer is a gallium nitride (GaN) film having a thickness of about 0.5 to 200 nm.

  The n-type semiconductor layer 21 is, for example, a GaN film having a thickness of about 5 μm doped with silicon (Si) as an n-type dopant, and supplies electrons to the active layer 22. The p-type semiconductor layer 23 is, for example, a GaN film having a thickness of about 0.2 μm doped with a p-type dopant, and supplies holes to the active layer 22. The p-type dopant is magnesium (Mg), zinc (Zn), cadmium (Cd), calcium (Ca), beryllium (Be), carbon (C), or the like.

  The active layer 22 has, for example, a multiple quantum well (MQW) structure in which InGaN films and GaN films are alternately stacked. The film thicknesses of the InGaN film and the GaN film are about several μm to several tens of μm, respectively. Electrons supplied from the n-type semiconductor layer 21 and holes supplied from the p-type semiconductor layer 23 are recombined in the active layer 22 to generate light.

The transparent electrode 30 and the electrode insulating film 40 are made of a material that transmits light generated in the active layer 22. For the transparent electrode 30, for example, an indium tin oxide (ITO) film can be employed. The thickness of the ITO film is about 50 nm to 500 nm. As the electrode insulating film 40, for example, a silicon oxide (SiO ₂ ) film having a film thickness of about 150 nm to 1500 nm can be employed.

  For the n-side electrode 51 and the p-side electrode 53, for example, gold (Au) can be used. Electrons are supplied to the n-side electrode 51 from a negative power source outside the semiconductor light emitting device 1, and holes are supplied to the p-side electrode 53 from the positive power source.

  For the reflective layer 70, for example, a silver palladium copper (APC) film, an Al film, or the like can be employed. The light emitted from the active layer 22 in the direction of the transparent electrode 30 is reflected by the reflective layer 70 and is emitted to the outside of the semiconductor light emitting device 1 as part of the output light L.

  As shown in FIG. 1, the reflective layer 70 is embedded in the electrode insulating film 40. For example, the reflective layer 70 is formed after the electrode insulating film 40 is formed halfway, and the remaining electrode insulating film 40 is formed on the reflective layer 70. For this reason, the metal of the reflective layer 70 is hardly exposed to the atmosphere, pure water, or the like for a long time, and deterioration of the reflective layer 70 due to water vapor or the like can be suppressed.

  FIG. 2 is a plan view of the semiconductor light emitting device 1 as viewed from the n-side electrode 51 and the p-side electrode 53 side. FIG. 1 is a cross-sectional view taken along the II direction of FIG. As shown in FIG. 2, the p-side electrode 53 is disposed on almost the entire top surface of the semiconductor light emitting device 1 except for the region where the n-side electrode 51 is disposed. Holes are supplied from the p-side electrode 53 to the transparent electrode 30 through the p-side opening 43 opened in the electrode insulating film 40.

  In FIG. 2, a region indicated by a broken line inside the n-side electrode 51 is an n-side opening 41 through the n-side electrode 51. Further, the alternate long and short dash line shown inside the n-side electrode 51 indicates the outer edge of the transparent electrode 30, and the transparent electrode 30 is not disposed in the region inside the alternate long and short dash line. The two-dot chain line shown inside the n-side electrode 51 represents the outer edge of the reflective layer 70, and the reflective layer 70 is not disposed in the region inside the two-dot chain line.

  As shown in FIGS. 1 and 2, the n-side electrode 51 is disposed above the n-side opening 41. The region of the n-side electrode 51 exposed on the upper surface of the semiconductor light emitting device 1 is used as an electrode pad for making electrical contact with an external negative power source such as a bonding pad. For this reason, the area of the n-side electrode 51 may be a size required for contact with the outside. Since the n-side electrode 51 is used as an electrode pad, it is not necessary to prepare an electrode pad different from the n-side electrode 51 that supplies electrons to the n-type semiconductor layer 21.

  As described above, in the semiconductor light emitting device 1, the n-side electrode 51 and the n-type semiconductor layer 21 are in contact with each other in the n-side opening 41 formed only immediately below the n-side electrode 51. For this reason, the area of the semiconductor light emitting device 1 does not increase, and a decrease in the region through which light emitted from the active layer 22 and traveling in the direction of the reflective layer 70 is transmitted is suppressed.

  As shown in FIG. 1, the opening area of the stacked body 20 in the n-side opening 41 has a tapered shape in which the side surface is inclined with respect to the bottom surface and the bottom surface is narrower than the frontage. For this reason, the electrode insulating film 40 does not become thin at the side surface portion of the stacked body 20 exposed at the n-side opening 41, and the semiconductor light emitting device 1 can be prevented from being broken by an external force. For example, even if the n-side electrode 51 is wire-bonded, the n-side opening 41 is not broken by the bonding pressure. Since the n-side opening 41 is located below the n-side electrode 51, it is originally a non-light emitting region, and even if the opening region of the stacked body 20 is tapered, the light emitting region is not substantially reduced.

  FIG. 2 shows an example in which two striped p-side openings 43 are arranged in parallel to each other. The number of p-side openings 43 can be arbitrarily set according to the area of the transparent electrode 30 and the like. For example, when it is necessary to supply holes to the transparent electrode 30 having a large area, three or more p-side openings 43 may be formed. On the other hand, when the area of the transparent electrode 30 is small, one p-side opening 43 may be formed.

  The p-side opening 43 is arranged so that holes supplied from the p-side electrode 53 are supplied to the entire area of the transparent electrode 30. Thereby, the current flowing through the active layer 22 is made uniform, and light can be generated in a wide range of the active layer 22.

  For example, as shown in FIG. 2, the distance d11 from the end of each of the two p-side openings 43 arranged to the corner of the p-side electrode 53 is preferably the same length. The distance d12 from the end of each p-side opening 43 to the outer edge of the transparent electrode 30 in the vicinity of the n-side opening 41 is preferably the same length. By arranging the p-side opening 43 in this way, holes are supplied uniformly throughout the transparent electrode 30, and the current flowing through the active layer 22 is made uniform.

  Unlike the semiconductor light emitting device 1 described above, when electrons are supplied to the entire area of the n-type semiconductor layer 21 in order to make the current flowing through the active layer 22 uniform, the semiconductor light emitting device 1 has a wide area on the upper surface. The n-side electrode 51 needs to be disposed. For example, the n-side electrode 51 is arranged in a comb tooth shape. In this case, it is necessary to form the n-side opening 41 which is a deep digging groove in a wide range on the upper surface of the semiconductor light emitting device 1. In addition, since the electrode insulating film 40 is formed on the inner wall of the n-side opening 41, the width of the n-side opening 41 needs to be increased.

  On the other hand, according to the semiconductor light emitting device 1 shown in FIGS. 1 and 2, holes are supplied from the p-side electrode 53 to the entire area of the transparent electrode 30 through the patterned p-side opening 43, and the active layer 22. Current flows uniformly. For this reason, the area of the n-side opening 41 can be reduced. Note that the depth of the p-side opening 43 may be the thickness of the electrode insulating film 40. Further, the width of the p-side opening 43 may be such that the p-side electrode 53 and the transparent electrode 30 can be in contact with each other, and does not need to be widened in order to form an insulating film inside the p-side opening 43.

  The area of the n-side opening 41 where the light generated in the active layer 22 is not reflected in the direction of the substrate 10 affects the area of the non-light emitting region of the semiconductor light emitting device 1. That is, as the area of the n-side opening 41 is larger, the effective area of the light emitting region 110 where the output light L having a high luminous intensity is radiated decreases. Therefore, according to the semiconductor light emitting device 1 according to the first embodiment, since the area of the n-side opening 41 can be reduced, it contributes to light emission as compared with the case where the n-side electrode 51 is widely disposed on the upper surface of the semiconductor light emitting device 1. The current flowing through the active layer 22 can be made uniform while suppressing the area reduction of the region to be performed. That is, according to the semiconductor light emitting device 1 according to the first embodiment, a reduction in the area of the light emitting region 110 where the output light L is effectively emitted is suppressed.

  Further, as shown in FIGS. 1 and 2, in the semiconductor light emitting device 1 according to the first embodiment, the active layer 22 and the p-type semiconductor layer 23 in the remaining region of the region where the n-side opening 41 is provided. The transparent electrode 30 and the reflective layer 70 are disposed below the n-side electrode 51. As described above, by arranging the transparent electrode 30 and the reflective layer 70 also below the outer edge of the n-side electrode 51, the light emitted from the active layer 22 is reflected also below the n-side electrode 51. Therefore, the region that contributes to the light emission of the semiconductor light emitting device 1 can be made up to the very edge of the n-side electrode 51. That is, almost the entire region other than the region where the n-side opening 41 is disposed is a region contributing to light emission. As a result, the ratio of the light emitting area to the substrate area of the semiconductor light emitting device 1 can be further increased. For this reason, the light generated in the active layer 22 can be radiated to the outside more efficiently, and a greater luminous intensity can be obtained.

  In addition, unlike the semiconductor light emitting device 1 shown in FIG. 1, when the n-side electrode 51 is widely disposed on the upper surface of the semiconductor light emitting device 1, it is disposed along the n-side opening 41 that is a deep digging groove. The n-side electrode 51 is used for current routing. For this reason, current concentrates on the corners of the n-side opening 41. As a result, there is a problem that electrostatic discharge (ESD) breakdown due to positive static electricity is likely to occur at the corner of the n-side opening 41.

  However, in the semiconductor light emitting device 1 according to the first embodiment, a current is drawn by the p-side opening 43. For this reason, the current is distributed to the transparent electrode 30 at a distance from the n-side electrode 51, and the current does not concentrate on a part of the electrode. Therefore, there is no place that is easily damaged by ESD, and as a result, the ESD resistance of the semiconductor light emitting device 1 is improved.

  The semiconductor light emitting device 1 shown in FIG. 1 is a flip chip type mounted on a mounting substrate 80 as shown in FIG. 3, for example. That is, the n-side electrode 51 and the p-side electrode 53 are in contact with the power supply wiring pattern on the mounting substrate 80, and the semiconductor light emitting device 1 is mounted on the mounting substrate 80.

  A power supply wiring pattern including a negative electrode region 81 and a positive electrode region 83 is formed on the mounting substrate 80. The region where the n-side electrode 51 and the p-side electrode 53 of the semiconductor light emitting device 1 are disposed is set corresponding to the power supply wiring pattern of the mounting substrate 80 on which the semiconductor light emitting device 1 is mounted. For example, when the semiconductor light emitting device 1 and the mounting substrate 80 are connected using eutectic solder such as gold tin (Au—Sn), the n-side electrode 51 and the p-side electrode 51 and the p-type electrode are connected to the power wiring pattern of the arbitrary mounting substrate 80. The pattern arrangement of the side electrode 53 is determined. Then, the semiconductor light emitting device 1 is mounted on the mounting substrate 80 so that the n-side electrode 51 is in contact with the negative electrode region 81 and the p-side electrode 53 is in contact with the positive electrode region 83.

  Electrons supplied from the negative electrode region 81 of the mounting substrate 80 are supplied to the n-type semiconductor layer 21 through the n-side electrode 51. Holes supplied from the positive electrode region 83 of the mounting substrate 80 are supplied to the p-type semiconductor layer 23 through the p-side electrode 53. These electrons and holes are recombined in the active layer 22 to generate light.

  As already described, the light generated in the active layer 22 and traveling in the direction of the substrate 10 is transmitted through the buffer layer 11 and the substrate 10, and as a part of the output light L from the light emitting region 110 of the substrate 10, the semiconductor light emitting device. 1 is radiated to the outside. The light generated in the active layer 22 and emitted in the direction of the transparent electrode 30 is reflected in the direction of the substrate 10 by the reflective layer 70. The light reflected by the reflective layer 70 is radiated to the outside as a part of the output light L from the light emitting region 110 of the substrate 10.

  As shown in FIGS. 1 and 3, the surface of the n-side electrode 51 and the surface of the p-side electrode 53 are on the same plane level. That is, there is almost no step on the surface of the semiconductor light emitting device 1 that is in contact with the mounting substrate 80. For this reason, when the semiconductor light emitting device 1 is mounted on the mounting substrate 80, it is not necessary to adjust the height of the n-side electrode 51 and the height of the p-side electrode 53 with bumps or conductive materials. Therefore, the semiconductor light emitting device 1 can be easily mounted on the mounting substrate 80.

  Since the contact area between the semiconductor light emitting device 1 and the mounting substrate 80 is wide, the heat dissipation of the semiconductor light emitting device 1 is also good.

  As described above, according to the semiconductor light emitting device 1 according to the first embodiment, the entire region of the transparent electrode 30 is passed from the p-side electrode 53 through the p-side opening 43 opened in the electrode insulating film 40. Are supplied with holes. For this reason, the current flowing through the active layer 22 is made uniform. On the other hand, the area of the region where the n-side electrode 51 is arranged is small, and the stacked body 20 is not removed except in the region where the n-side opening 41 just below the n-side electrode 51 is formed. The transparent electrode 30 and the reflective layer 70 are disposed. For this reason, the ratio of the light emitting area to the substrate area in the semiconductor light emitting device 1 is high.

  Furthermore, by embedding the reflective layer 70 of the semiconductor light emitting device 1 inside the electrode insulating film 40, the moisture resistance of the reflective layer 70 can be improved.

  A method for manufacturing the semiconductor light emitting device 1 shown in FIG. 1 will be described with reference to FIGS. In addition, the manufacturing method of the semiconductor light-emitting device 1 described below is an example, and it is needless to say that it can be realized by various other manufacturing methods including this modification.

  (A) First, the buffer layer 11 is formed on the substrate 10. On the buffer layer 11, an n-type semiconductor layer 21, an active layer 22, and a p-type semiconductor layer 23 are sequentially stacked to form a stacked body 20 as shown in FIG.

  (B) The transparent electrode 30 is formed on the p-type semiconductor layer 23. In order to delete the transparent electrode 30 in the region where the n-side opening 41 is formed, the transparent electrode 30 is patterned as shown in FIG. 5 using a photolithography technique or the like.

  (C) As shown in FIG. 6, the p-type semiconductor layer 23, the active layer 22, and the upper part of the n-type semiconductor layer 21 in the region where the n-side opening 41 is formed are removed, and the stacked body 20 An opening region 410 is formed. At this time, as shown in FIG. 6, a part of the upper portion of the stacked body 20 is removed so that the opening region 410 has a tapered shape.

  (D) As shown in FIG. 7, a lower layer portion 401 of the electrode insulating film 40 is formed on the transparent electrode 30. Next, the reflective layer 70 is formed on the lower layer portion 401.

  (E) The reflective layer 70 and the lower layer portion 401 in the region where the n-side opening 41 and the p-side opening 43 are disposed are removed using a photolithography technique or the like. Next, the upper layer portion 402 of the electrode insulating film 40 is formed on the reflective layer 70 and the lower layer portion 401. And as shown in FIG. 8, the upper layer part 402 of the area | region which arrange | positions the n side opening part 41 and the p side opening part 43 is removed. Note that only the reflective layer 70 may be removed first, and the upper layer portion 402 and the lower layer portion 401 may be simultaneously removed after the upper layer portion 402 is formed.

  (F) A metal film is formed on the electrode insulating film 40 so as to bury the n-side opening 41 and the p-side opening 43 formed in the electrode insulating film 40. Thereafter, as shown in FIG. 9, the metal film is patterned to form the n-side electrode 51 and the p-side electrode 53. Thereby, the semiconductor light emitting device 1 shown in FIG. 1 is completed.

  Note that the flip-chip type semiconductor light emitting device 1 shown in FIG. 1 that emits the output light L from the substrate 10, the transparent electrode 30, and the electrode insulation can be obtained simply by changing the pattern arrangement of the n-side electrode 51 and the p-side electrode 53. A top-emitting semiconductor light-emitting device that emits output light that has passed through the film 40 can be made separately. That is, the flip chip type semiconductor light emitting device 1 and the top emission type light emitting device can be selected simply by changing the mask of the metal film for forming the n side electrode 51 and the p side electrode 53 and selecting whether or not the reflective layer 70 is formed. The semiconductor light emitting device can be selectively manufactured. For this reason, it is easy to obtain the process sharing effect.

<Modification>
As shown in FIG. 10, the semiconductor light emitting device 1 and the mounting substrate 80 may be connected by bumps 91 and 93. The bump 91 disposed on the negative electrode region 81 of the power supply wiring pattern and the n-side electrode 51 are in contact with each other, and the bump 93 disposed on the positive electrode region 83 is in contact with the p-side electrode 53.

  Further, in the semiconductor light emitting device 1 according to the first embodiment, it is not necessary to form a digging groove, so that the area of the n-side opening 41 of the semiconductor light emitting device 1 is small. For this reason, the freedom degree of the position which arrange | positions the n side electrode 51 especially is high. Therefore, the n-side electrode 51 can be arranged at an arbitrary position according to the power supply wiring pattern of the mounting substrate 80.

  FIG. 11 shows an arrangement example of the n-side electrode 51 and the p-side electrode 53 which is different from that in FIG. Although FIG. 2 shows an example in which one n-side opening 41 is arranged, FIG. 11 shows an example in which three n-side openings 41 are arranged. In FIG. 11, the n-side electrode 51 is arranged in a band shape covering the three n-side openings 41. A p-side electrode 53 is disposed on both sides of the n-side electrode 51.

(Second Embodiment)
In the semiconductor light emitting device 1 according to the second embodiment of the present invention, the reflection layer 70 is disposed between the transparent electrode 30 and the electrode insulating film 40 as shown in FIG. 1 is different from the semiconductor light emitting device 1 shown in FIG. Other configurations are the same as those of the first embodiment shown in FIG.

  That is, the stacked body 20 is not removed except in the region where the n-side opening 41 directly under the n-side electrode 51 is formed, and the transparent electrode 30 and the reflective layer 70 are disposed below the n-side electrode 51. For this reason, the ratio of the light emitting area to the substrate area in the semiconductor light emitting device 1 shown in FIG. 12 is high.

  Also, as shown in FIG. 12, by forming the electrode insulating film 40 so as to cover the reflective layer 70, deterioration of the reflective layer 70 due to water vapor or the like can be suppressed. For this reason, the moisture resistance of the reflective layer 70 is improved.

  A method for manufacturing the semiconductor light emitting device 1 according to the second embodiment of the present invention will be described with reference to FIGS. In addition, the manufacturing method of the semiconductor light-emitting device 1 described below is an example, and it is needless to say that it can be realized by various other manufacturing methods including this modification.

  (A) In the same manner as described with reference to FIGS. 4 to 5, the substrate 10, the buffer layer 11, and the stacked body 20 are stacked, and then the transparent electrode 30 is formed on the p-type semiconductor layer 23. Then, as shown in FIG. 13, the reflective layer 70 is laminated | stacked on the transparent electrode 30 patterned so that it may not be arrange | positioned in the area | region in which the n side opening part 41 is formed. At this time, the reflective layer 70 is protected by forming the protective layer 75 made of, for example, a titanium (Ti) film and a silicon oxide film on the reflective layer 70.

  (B) The p-type semiconductor layer 23, the active layer 22, and a part of the upper portion of the n-type semiconductor layer 21 in the region where the n-side opening 41 is formed are removed to form the opening region 410 of the stacked body 20. At this time, as shown in FIG. 14, a part of the upper part of the stacked body 20 is removed so that the opening region 410 has a tapered shape.

  (C) As shown in FIG. 15, the electrode insulating film 40 is formed on the upper surfaces of the stacked body 20 and the protective layer 75.

  (D) As shown in FIG. 16, the electrode insulating film 40 in the region where the n-side opening 41 and the p-side opening 43 are disposed is removed using a photolithography technique or the like. At this time, the protective layer 75 exposed on the bottom surface of the p-side opening 43 is also removed. The reflective layer 70 exposed on the bottom surface of the p-side opening 43 may be removed or left.

  (E) A metal film is formed on the electrode insulating film 40 so as to bury the n-side opening 41 and the p-side opening 43 formed in the electrode insulating film 40. Thereafter, as shown in FIG. 17, the metal film is patterned to form the n-side electrode 51 and the p-side electrode 53. Thus, the semiconductor light emitting device 1 shown in FIG. 12 is completed.

  According to the semiconductor light emitting device 1 according to the second embodiment of the present invention, it is possible to provide a semiconductor light emitting device in which the ratio of the light emitting area to the substrate area is high and the moisture resistance of the reflective layer 70 is improved. Others are substantially the same as those in the embodiment, and redundant description is omitted.

  As mentioned above, although this invention was described by embodiment, it should not be understood that the description and drawing which form a part of this indication limit this invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art. Needless to say, the present invention includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor light-emitting device 10 ... Board | substrate 11 ... Buffer layer 20 ... Laminated body 21 ... N-type semiconductor layer 22 ... Active layer 23 ... P-type semiconductor layer 30 ... Transparent electrode 40 ... Electrode insulating film 41 ... N side opening part 43 ... p Side opening 51 ... n-side electrode 53 ... p-side electrode 70 ... reflection layer 80 ... mounting substrate 81 ... negative electrode region 83 ... positive electrode region 91, 93 ... bump 110 ... light emitting region

Claims (3)

a stacked body in which an n-type semiconductor layer, an active layer, and a p-type semiconductor layer are stacked in this order;
A transparent electrode disposed on the p-type semiconductor layer;
An electrode insulating film disposed on the transparent electrode;
An n-side electrode disposed on the electrode insulating film and in contact with the n-type semiconductor layer at an n-side opening provided through the electrode insulating film, the transparent electrode, the p-type semiconductor layer, and the active layer; ,
A p-side electrode disposed on the electrode insulating film and spaced apart from the n-side electrode, and in contact with the transparent electrode at a striped p-side opening provided in the electrode insulating film;
A reflective layer that is disposed inside the electrode insulating film or between the transparent electrode and the electrode insulating film so as to face the upper surface of the multilayer body and reflects light emitted from the active layer;
The n-side opening has a tapered shape whose bottom is narrower than the frontage,
Below the outer edge portion of the n-side electrode, the active layer, the transparent electrode, and the reflective layer are disposed around the periphery of the n-side opening ,
The reflective layer has a region disposed inside the n-side opening along the tapered slope of the n-side opening,
The n-side electrode has a region disposed on the inner side of the n-side opening along the bottom surface from the tapered slope of the n-side opening, and at the bottom surface of the n-side opening, in contact with the n-type semiconductor layer,
The semiconductor light emitting device, wherein the reflective layer and the n-side electrode are made of different materials .   The semiconductor light emitting device according to claim 1, wherein the p-side electrode is in contact with the transparent electrode at the plurality of stripe-shaped p-side openings arranged in parallel to each other.   3. The semiconductor light emitting device according to claim 1, wherein the surface of the n-side electrode and the surface of the p-side electrode are at the same plane level.

Images