JP2017050329A - Semiconductor device and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device and a manufacturing method, which can protect anti-reflection structure.SOLUTION: A semiconductor device comprises: a semiconductor layer 15; a light transmissive layer 31 which has a plurality of first salients 71 and second salients 72 with a height higher than a height of the first salient 71 and consists primarily of a material having a first Young's modulus; and a second light transmissive layer 32 which is provided between the semiconductor layer 15 and the first light transmissive layer 31 and consists primarily of a material having a second Young's modulus higher than the first Young's modulus.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a semiconductor device and a method for manufacturing the same.

  A semiconductor device in which an antireflection structure is provided on the surface of an optical device such as an LED (Light Emitting Diode) has been proposed. Since the antireflection structure is a fine concavo-convex structure, there is a concern about damage during the manufacturing process of the semiconductor device. Damage to the antireflection structure can reduce the light extraction efficiency and light capture efficiency of the optical device.

JP 2008-300501 A

  Embodiments provide a semiconductor device and a manufacturing method capable of protecting an antireflection structure.

  According to the embodiment, the semiconductor device includes a semiconductor layer, a plurality of first protrusions, and a second protrusion having a height equal to or higher than the height of the first protrusion, and has a first Young's modulus. A first light transmission layer containing as a main component a material having a second Young's modulus higher than the first Young's modulus provided between the semiconductor layer and the first light transmission layer as a main component. A second light transmission layer.

(A) is a schematic cross section of the semiconductor light emitting device of the embodiment, (b) is a schematic top view of the semiconductor light emitting device of the embodiment. (A) is a schematic plan view which shows the layout of the electrode of the semiconductor light-emitting device of embodiment, (b) is a schematic bottom view of the semiconductor light-emitting device of embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 6 is a schematic cross-sectional view of another example of the first light transmission layer of the semiconductor light emitting device of the embodiment. FIG. 6 is a schematic cross-sectional view of another example of the first light transmission layer of the semiconductor light emitting device of the embodiment. The schematic plan view of the other example of the 1st light transmission layer of the semiconductor light-emitting device of embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment. FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the semiconductor light emitting device of the embodiment.

Hereinafter, embodiments will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same element in each drawing.
In the present embodiment, a semiconductor light emitting device will be described as an example of the semiconductor device.

FIG. 1A is a schematic cross-sectional view of the semiconductor light emitting device of the embodiment. FIG. 1A corresponds to the AA ′ cross section in FIG.
FIG. 1B is a schematic plan view of the light extraction surface (the upper surface of the semiconductor light emitting device in FIG. 1A) of the semiconductor light emitting device of the embodiment.

FIG. 2A is a schematic plan view illustrating an example of a planar layout of the p-side electrode 16 and the n-side electrode 17 in the semiconductor light emitting device of the embodiment. FIG. 1A corresponds to the BB ′ cross section in FIG. FIG. 2A corresponds to a view of the second surface side of the semiconductor layer 15 with the wiring portions 41 and 43, the resin layer 25, the insulating film 18, and the reflective film 51 in FIG. 2A corresponds to a top view of the stacked body (excluding the substrate 10) in FIG. 4B.
FIG. 2B is a schematic plan view of the mounting surface of the semiconductor light emitting device of the embodiment (the lower surface of the semiconductor light emitting device of FIG. 1A).

  The semiconductor light emitting device of the embodiment includes a semiconductor layer 15 having a light emitting layer 13. The semiconductor layer 15 has a first surface 15a and a second surface 15b on the opposite side (see FIG. 3A).

  The semiconductor layer 15 includes a first semiconductor layer 11, a second semiconductor layer 12, and a light emitting layer 13. The light emitting layer 13 is provided between the first semiconductor layer 11 and the second semiconductor layer 12. The first semiconductor layer 11 and the second semiconductor layer 12 include, for example, gallium nitride.

  The first semiconductor layer 11 includes, for example, a base buffer layer and an n-type GaN layer. The second semiconductor layer 12 includes, for example, a p-type GaN layer. The light emitting layer 13 includes a material that emits blue, purple, blue purple, ultraviolet light, or the like. The emission peak wavelength of the light emitting layer 13 is, for example, 430 to 470 nm.

  The second surface side of the semiconductor layer 15 is processed into an uneven shape. The convex portion is a portion 15 e including the light emitting layer 13, and the concave portion is a portion 15 f not including the light emitting layer 13. The surface of the portion 15 e including the light emitting layer 13 is the surface of the second semiconductor layer 12, and the p-side electrode 16 is provided on the surface of the second semiconductor layer 12. The surface of the portion 15 f not including the light emitting layer 13 is the surface of the first semiconductor layer 11, and the n-side electrode 17 is provided on the surface of the first semiconductor layer 11.

  On the second surface of the semiconductor layer 15, the area of the portion 15 e including the light emitting layer 13 is larger than the area of the portion 15 f not including the light emitting layer 13. In addition, the area of the p-side electrode 16 provided on the surface of the portion 15 e including the light emitting layer 13 is wider than the area of the n-side electrode 17 provided on the surface of the portion 15 f not including the light emitting layer 13. Thereby, a wide light emitting surface can be obtained, and the light output can be increased.

  In the example shown in FIG. 2A, the portion 15 f that does not include the light emitting layer 13 surrounds the portion 15 e that includes the light emitting layer 13, and the n-side electrode 17 surrounds the p-side electrode 16.

  As shown in FIG. 2A, the n-side electrode 17 has, for example, four straight portions, and one of the straight portions is provided with a contact portion 17c protruding in the width direction of the straight portion. ing. An n-side wiring layer 22 is connected to the surface of the contact portion 17c as shown in FIG.

  A current is supplied to the light emitting layer 13 through the p-side electrode 16 and the n-side electrode 17, and the light emitting layer 13 emits light. And the light radiated | emitted from the light emitting layer 13 is radiate | emitted outside the semiconductor light-emitting device from the 1st surface 15a side.

  A support body 100 is provided on the second surface side of the semiconductor layer 15 as shown in FIG. The light emitting element including the semiconductor layer 15, the p-side electrode 16, and the n-side electrode 17 is supported by a support body 100 provided on the second surface side.

  A phosphor layer (second light transmission layer) 32 is provided on the first surface 15 a side of the semiconductor layer 15. The phosphor layer 32 includes a plurality of particulate phosphors 32a. The phosphor 32 a is excited by the emitted light of the light emitting layer 13 and emits light having a wavelength different from that of the emitted light of the light emitting layer 13.

  The plurality of phosphors 32a are integrated by a binding material 32b. The binding material 32b is transparent to the emitted light of the light emitting layer 13 and the emitted light of the phosphor 32a. In this specification, “transmission” is not limited to 100% transmittance, but includes a case where a part of light is absorbed. The binding material 32b is, for example, a silicone resin. Alternatively, glass can be used as the binder 32b.

  A first light transmission layer 31 is provided on the phosphor layer 32. The first light transmission layer 31 is transparent to the emitted light of the light emitting layer 13 and the emitted light of the phosphor 32a.

  As shown in FIGS. 1A and 1B, the first light transmission layer 31 has a so-called moth-eye structure in which irregularities are repeated with a period of nm order. That is, the first light transmission layer 31 has a plurality of first protrusions 71. In the example shown in FIG. 1A, the first convex portion 71 is, for example, a substantially bullet-shaped.

  The first light transmission layer 31 formed with such a plurality of first protrusions 71 suppresses reflection of the emitted light of the light emitting layer 13 and the emitted light of the phosphor 32a. The first light transmission layer 31 suppresses reflection of visible light, for example, and improves the light extraction efficiency of the semiconductor light emitting device.

  The first light transmission layer 31 further has a second protrusion 72. The 2nd convex part 72 is provided in the outer peripheral side of the semiconductor light-emitting device, and as shown in FIG.1 (b), it forms in the shape of a line surrounding the area | region in which the some 1st convex part 71 was provided.

  The height of the second convex portion 72 is not less than the height of the first convex portion 71. In the example shown in FIG. 1A, the height of the second convex portion 72 is higher than the height of the first convex portion 71. Here, the “height” represents the height with reference to the upper surface of the phosphor layer (second light transmission layer) 32 underlying the first light transmission layer 31.

  The top portion of the second convex portion 72 has a flat region having a larger area than the top portion of one first convex portion 71.

  The 1st convex part 71 and the 2nd convex part 72 are integrally provided with the same material. The first light transmission layer 31 including the first convex portion 71 and the second convex portion 72 is made of a material containing, for example, a silicone resin as a main component.

  The binder 32b of the phosphor layer 32 is also made of a material containing, for example, a silicone resin as a main component. However, even with the same silicone resin material, the Young's modulus (first Young's modulus) of the first light transmitting layer 31 is lower than the Young's modulus (second Young's modulus) of the binder 32b of the phosphor layer 32.

  That is, the first light transmission layer 31 containing a material having a first Young's modulus as a main component is more than the binder 32b of the phosphor layer 32 containing a material having a second Young's modulus higher than the first Young's modulus as a main component. Also soft.

  As shown in FIG. 1A, an insulating film (first insulating film) 18 is provided on the second surface side of the semiconductor layer 15. The insulating film 18 is an inorganic insulating film such as a silicon oxide film, for example. The insulating film 18 covers a part of the p-side electrode 16 and a part of the n-side electrode 17. The insulating film 18 is also provided on the side surface of the light emitting layer 13 and the side surface of the second semiconductor layer 12 and covers these side surfaces.

  Further, the insulating film 18 is also provided on the side surface (side surface of the first semiconductor layer 11) 15c continuing from the first surface 15a in the semiconductor layer 15, and covers the side surface 15c. The insulating film 18 extends from the side surface 15 c toward the outer periphery of the chip around the semiconductor layer 15.

  On the insulating film 18, a p-side wiring layer 21 as a first wiring layer and an n-side wiring layer 22 as a second wiring layer are provided apart from each other. As shown in FIG. 5B, a plurality of first openings 18 a that communicate with the p-side electrode 16 and second openings 18 b that communicate with the contact portion 17 c of the n-side electrode 17 are formed in the insulating film 18.

  The p-side wiring layer 21 is provided on the insulating film 18 and in the first opening 18a. The p-side wiring layer 21 is electrically connected to the p-side electrode 16 through a via 21a (FIG. 6B) provided in the first opening 18a.

  The n-side wiring layer 22 is provided on the insulating film 18 and in the second opening 18b. The n-side wiring layer 22 is electrically connected to the contact portion 17c of the n-side electrode 17 through a via 22a (FIG. 6B) provided in the second opening 18b.

  The p-side wiring layer 21 and the n-side wiring layer 22 occupy most of the region on the second surface side and spread on the insulating film 18. The p-side wiring layer 21 is connected to the p-side electrode 16 through a plurality of vias 21a.

  The reflective film 51 covers the side surface 15 c of the semiconductor layer 15 via the insulating film 18. The reflective film 51 is not in contact with the side surface 15 c and is not electrically connected to the semiconductor layer 15. The reflective film 51 is separated from the p-side wiring layer 21 and the n-side wiring layer 22. The reflective film 51 is reflective to the emitted light of the light emitting layer 13 and the emitted light of the phosphor 32a.

  The reflective film 51, the p-side wiring layer 21, and the n-side wiring layer 22 include a copper film that is simultaneously formed on the common metal film 60 shown in FIG.

  For example, a copper film constituting the reflection film 51, the p-side wiring layer 21 and the n-side wiring layer 22 is formed on the metal film 60 formed on the insulating film 18 by plating.

  The metal film 60 includes a base metal film 61, an adhesion layer 62, and a seed layer 63, which are sequentially stacked from the insulating film 18 side.

  The base metal film 61 is, for example, an aluminum film having high reflectivity with respect to the emitted light of the light emitting layer 13. The seed layer 63 is a copper film for depositing copper by plating. The adhesion layer 62 is, for example, a titanium film having excellent wettability with respect to both aluminum and copper.

  Note that the reflective film 51 may be formed of the metal film 60 without forming the plating film (copper film) on the metal film 60 in the outer periphery of the chip adjacent to the side surface 15 c of the semiconductor layer 15. Since the reflective film 51 includes at least the aluminum film 61, the reflective film 51 has a high reflectance with respect to the emitted light of the light emitting layer 13 and the emitted light of the phosphor 32a.

  Since the underlying metal film (aluminum film) 61 is also left under the p-side wiring layer 21 and the n-side wiring layer 22, the aluminum film 61 is formed so as to spread over most of the region on the second surface side. Thereby, the quantity of the light which goes to the fluorescent substance layer 32 side can be increased.

  A p-side metal pillar 23 is provided on the surface of the p-side wiring layer 21 opposite to the semiconductor layer 15. The p-side wiring layer 21 and the p-side metal pillar 23 form a p-side wiring portion 41. An n-side metal pillar 24 is provided on the surface of the n-side wiring layer 22 opposite to the semiconductor layer 15. The n-side wiring layer 22 and the n-side metal pillar 24 form an n-side wiring portion 43.

  A resin layer (second insulating film) 25 is provided between the p-side metal pillar 23 and the n-side metal pillar 24, around the p-side metal pillar 23, and around the n-side metal pillar 24. 23 and the side surface of the n-side metal pillar 24 are covered. The resin layer 25 is also provided on the outer periphery of the chip adjacent to the side surface 15 c of the semiconductor layer 15 and covers the reflective film 51.

  As will be described later, the semiconductor layer 15 is formed on the substrate by an epitaxial growth method. The substrate is removed after forming the support body 100 including the p-side metal pillar 23, the n-side metal pillar 24, and the resin layer 25, and the substrate is not provided on the first surface 15 a side of the semiconductor layer 15. The semiconductor layer 15 is not supported by a rigid plate-like substrate, but is supported by a support body 100 made of a composite of metal pillars 23 and 24 and a resin layer 25.

  An end (surface) opposite to the p-side wiring layer 21 in the p-side metal pillar 23 is exposed from the resin layer 25 and functions as a p-side external terminal 23a that can be connected to an external circuit such as a mounting substrate. An end (surface) opposite to the n-side wiring layer 22 in the n-side metal pillar 24 is exposed from the resin layer 25 and functions as an n-side external terminal 24a that can be connected to an external circuit such as a mounting board. The p-side external terminal 23a and the n-side external terminal 24a are joined to the land of the mounting board via, for example, solder.

  Due to a thermal cycle during mounting of the semiconductor light emitting device, stress due to solder or the like that joins the p-side external terminal 23a and the n-side external terminal 24a to the land of the mounting substrate is applied to the semiconductor layer 15. The p-side metal pillar 23, the n-side metal pillar 24, and the resin layer 25 absorb and relax the stress. In particular, the stress relaxation effect can be enhanced by using a resin layer 25 that is more flexible than the semiconductor layer 15 as a part of the support 100.

  Next, with reference to FIGS. 3A to 10B, a method for manufacturing the semiconductor light emitting device of the embodiment will be described.

  As shown in FIG. 3A, the first semiconductor layer 11, the light emitting layer 13, and the second semiconductor layer 12 are epitaxially grown in order on the main surface of the substrate 10 by, for example, MOCVD (metal organic chemical vapor deposition). The

  In the semiconductor layer 15 including the first semiconductor layer 11, the light emitting layer 13, and the second semiconductor layer 12, the substrate 10 side is the first surface 15a, and the opposite side of the substrate 10 is the second surface 15b.

  The substrate 10 is, for example, a silicon substrate. Alternatively, the substrate 10 may be a sapphire substrate. The semiconductor layer 15 is a nitride semiconductor layer containing gallium nitride (GaN), for example.

  FIG. 3B shows a state where the second semiconductor layer 12 and the light emitting layer 13 are selectively removed. For example, the second semiconductor layer 12 and the light emitting layer 13 are selectively etched by RIE (Reactive Ion Etching) to expose a part of the first semiconductor layer 11.

  Next, as shown in FIG. 4A, the first semiconductor layer 11 is selectively removed to form a groove 90. For example, the semiconductor layer 15 is separated into a plurality of grooves 90 in a lattice pattern.

  The groove 90 penetrates the semiconductor layer 15 and reaches the substrate 10. At this time, the main surface of the substrate 10 is also slightly etched, and the bottom surface of the groove 90 may recede below the interface between the substrate 10 and the semiconductor layer 15. The groove 90 may be formed after the p-side electrode 16 and the n-side electrode 17 are formed.

  Next, as shown in FIG. 4B, the p-side electrode 16 is formed on the surface of the second semiconductor layer 12. An n-side electrode 17 is formed on the surface of the first semiconductor layer 11 in a region where the second semiconductor layer 12 and the light emitting layer 13 are selectively removed.

  The p-side electrode 16 formed in the region where the light emitting layer 13 is laminated includes a reflective film that reflects the emitted light of the light emitting layer 13. For example, the p-side electrode 16 includes silver, a silver alloy, aluminum, or an aluminum alloy. In order to prevent sulfidation and oxidation of the reflective film, the p-side electrode 16 further includes a metal protective film (barrier metal).

  Next, as illustrated in FIG. 5A, the insulating film 18 is formed so as to cover the stacked body provided on the substrate 10. The insulating film 18 covers the second surface 15 b of the semiconductor layer 15, the p-side electrode 16 and the n-side electrode 17. The insulating film 18 covers the side surface 15 c following the first surface 15 a of the semiconductor layer 15. Further, the insulating film 18 is also formed on the surface of the substrate 10 on the bottom surface of the groove 90.

  The insulating film 18 is, for example, a silicon oxide film or a silicon nitride film formed by a CVD (Chemical Vapor Deposition) method. In the insulating film 18, for example, a first opening 18a and a second opening 18b are formed by wet etching using a resist mask, as shown in FIG. The first opening 18 a reaches the p-side electrode 16, and the second opening 18 b reaches the contact portion 17 c of the n-side electrode 17.

  After patterning the insulating film 18, a metal is formed on the surface of the insulating film 18, the inner wall (side wall and bottom surface) of the first opening 18 a, and the inner wall (side wall and bottom surface) of the second opening 18 b as shown in FIG. A film 60 is formed. As shown in FIG. 6A, the metal film 60 includes an aluminum film 61, a titanium film 62, and a copper film 63. The metal film 60 is formed by, for example, a sputtering method.

  After the resist mask 91 shown in FIG. 6B is selectively formed on the metal film 60, the p-side wiring layer 21, n is formed by electrolytic copper plating using the copper film 63 of the metal film 60 as a seed layer. The side wiring layer 22 and the reflective film 51 are formed.

  The p-side wiring layer 21 is also formed in the first opening 18 a and is electrically connected to the p-side electrode 16. The n-side wiring layer 22 is also formed in the second opening 18 b and is electrically connected to the contact portion 17 c of the n-side electrode 17.

  Next, after removing the resist mask 91 using, for example, a solvent or oxygen plasma, a resist mask 92 shown in FIG. 7A is selectively formed. Alternatively, the resist mask 92 may be formed without removing the resist mask 91.

  After forming the resist mask 92, the p-side metal pillar 23 and the n-side metal pillar 24 are formed by electrolytic copper plating.

  The p-side metal pillar 23 is formed on the p-side wiring layer 21. The p-side wiring layer 21 and the p-side metal pillar 23 are integrated with the same copper material. The n-side metal pillar 24 is formed on the n-side wiring layer 22. The n-side wiring layer 22 and the n-side metal pillar 24 are integrated with the same copper material.

  The resist mask 92 is removed using, for example, a solvent or oxygen plasma. At this point, the p-side wiring layer 21 and the n-side wiring layer 22 are connected via the metal film 60. Further, the p-side wiring layer 21 and the reflective film 51 are also connected via the metal film 60, and the n-side wiring layer 22 and the reflective film 51 are also connected via the metal film 60.

  Therefore, the metal film 60 between the p-side wiring layer 21 and the n-side wiring layer 22, the metal film 60 between the p-side wiring layer 21 and the reflective film 51, and the n-side wiring layer 22 and the reflective film 51 The intervening metal film 60 is removed by etching.

  Thereby, the electrical connection between the p-side wiring layer 21 and the n-side wiring layer 22, the electrical connection between the p-side wiring layer 21 and the reflective film 51, and the reflection with the n-side wiring layer 22 through the metal film 60. The electrical connection with the film 51 is broken (FIG. 7B).

  Next, the resin layer 25 shown in FIG. 8A is formed on the structure shown in FIG. The resin layer 25 covers the p-side wiring part 41, the n-side wiring part 43, and the reflective film 51.

  The resin layer 25 constitutes the support body 100 together with the p-side wiring part 41 and the n-side wiring part 43. With the semiconductor layer 15 supported on the support 100, the substrate 10 is removed (FIG. 8B).

  For example, the substrate 10 which is a silicon substrate is removed by dry etching or wet etching. Alternatively, when the substrate 10 is a sapphire substrate, it can be removed by a laser lift-off method.

  The semiconductor layer 15 epitaxially grown on the substrate 10 may contain a large internal stress. Since the p-side metal pillar 23, the n-side metal pillar 24, and the resin layer 25 are flexible materials compared to the semiconductor layer 15 made of, for example, a GaN-based material, the internal stress during epitaxial growth is released at once when the substrate 10 is removed. Even so, the p-side metal pillar 23, the n-side metal pillar 24, and the resin layer 25 absorb the stress. For this reason, damage to the semiconductor layer 15 in the process of removing the substrate 10 can be avoided.

  By removing the substrate 10, the first surface 15a of the semiconductor layer 15 is exposed. The exposed first surface 15a is subjected to a roughening process (frost process) to form minute irregularities. For example, the first surface 15a is wet etched. In this etching, a difference in etching rate depending on the crystal plane orientation occurs. For this reason, micro unevenness | corrugation can be formed in the 1st surface 15a. By forming minute irregularities on the first surface 15a, the radiation light extraction efficiency of the light emitting layer 13 can be improved.

  As shown in FIG. 9A, the phosphor layer 32 is formed on the first surface 15a with the insulating film 19 interposed therebetween. The phosphor layer 32 is formed by a method such as printing, potting, molding, or compression molding. The insulating film 19 improves the adhesion between the semiconductor layer 15 and the phosphor layer 32.

  The phosphor layer 32 is also formed on a region around the side surface 15 c of the semiconductor layer 15. A resin layer 25 is also provided in a region around the side surface 15 c of the semiconductor layer 15. A phosphor layer 32 is formed on the resin layer 25 via the insulating film 18.

  A first light transmission layer 31 is formed on the phosphor layer 32 as shown in FIG. As shown in FIG. 1A, the first light transmission layer 31 is formed with a concavo-convex pattern including a first convex portion 71 and a second convex portion 72. A specific method for forming the first convex portion 71 and the second convex portion 72 will be described later in detail.

  After forming the first light transmission layer 31, the surface of the resin layer 25 (the lower surface in FIG. 9A) is ground, and as shown in FIG. 9B, the p-side metal pillar 23 and the n-side metal pillar 24. Is exposed from the resin layer 25. The exposed surface of the p-side metal pillar 23 becomes a p-side external terminal 23a, and the exposed surface of the n-side metal pillar 24 becomes an n-side external terminal 24a.

  Each process until the first convex portion 71 and the second convex portion 72 of the first light transmission layer 31 are formed is performed in a lump in a wafer state. Therefore, the wiring layer 21 is provided for each individual device separated into individual pieces. , 22, pillars 23, 24, packaging with the resin layer 25, phosphor layer 32, and first light transmission layer 31 need not be formed, and the cost can be greatly reduced. .

  As shown in FIG. 10A, the wafer on which the above-described structure is formed is supported on a stage 110 and singulated into a plurality of devices using a blade or a laser. The wafer is cut while the first light transmission layer 31 is pressed against the stage 110.

  According to the embodiment, the height h <b> 2 of the second protrusion 72 of the first light transmission layer 31 is higher than the height h <b> 1 of the first protrusion 71. Therefore, at the time of dicing, the tip of the second convex portion 72 contacts the stage 110, and the first convex portion 71 does not contact the stage 110. Therefore, no mechanical pressure is applied to the first convex portion 71, and damage to the first convex portion 71 is suppressed. The plurality of first protrusions 71 are designed to have a desired pitch and height so as to suppress reflection of light. The function of improving the light extraction efficiency by the first convex portion 71 can be appropriately exhibited.

  The second convex portion 72 includes, for example, a silicone resin as a main component that is softer (lower Young's modulus) than, for example, a silicone resin used for the phosphor layer 32, and is easily elastically deformed. The mechanical pressure received from the stage 110 is relieved by the elastic deformation of the second convex part 72, and the damage of the second convex part 72 itself can be suppressed.

  Even if the height h2 of the second convex portion 72 is the same as the height h1 of the first convex portion 71, the tip end portion of the second convex portion 72 contacts the stage 110, and is received from the stage 110. The mechanical pressure can be distributed to the second convex portion 72, and the force applied to the first convex portion 71 can be reduced.

  The separated semiconductor light emitting device is vacuum picked up using, for example, a collet 120 as shown in FIG. According to the embodiment, the front end surface 120 a of the collet 120 can be easily brought into contact with the upper surface of the second convex portion 72 that is higher than the first convex portion 71.

  As shown in FIG. 1B, since the second convex portion 72 is formed in a pattern closed in a plan view, a negative pressure is surely generated in the region surrounded by the second convex portion 72, and semiconductor light emission is performed. The device can be easily picked up. Further, the second convex portion 72 is elastically deformed, so that the adhesion between the tip surface 120 a of the collet 120 and the upper surface of the second convex portion 72 can be enhanced. That is, a gap is hardly formed between the tip surface 120a of the collet 120 and the upper surface of the second convex portion 72, and pickup using negative pressure is facilitated. Thus, the 2nd convex part 72 improves workability | operativity when picking up the device separated into pieces.

  FIGS. 11A to 11C are schematic cross-sectional views illustrating other examples of the second convex portion of the first light transmission layer 31. FIGS. 11A to 11C show the pick-up process by the collet 120 as in FIG. 10B.

The 2nd convex part 72a shown to Fig.11 (a) has the plane part 72ap at the front-end | tip part (top part).
The shape of the second convex portion 72 b shown in FIG. 11B is substantially a bullet shape like the shape of the first convex portion 71.
The 2nd convex part 72c shown in FIG.11 (c) has the plane part 72cp in the front-end | tip part (top part).

  The bullet-shaped second convex portion 72b contacts the tip surface 120a of the collet 120 in a state close to a point contact, whereas the second convex portion 72a having the flat surface portion 72ap and the second convex portion 72cp having the flat surface portion 72cp. The convex part 72c can make the contact area with the front end surface 120a of the collet 120 wider than the bullet-shaped second convex part 72b. This increase in the contact area improves the adhesion between the second protrusions 72a and 72b and the tip surface 120a of the collet 120, and the collet 120 uses negative pressure generated in the area inside the second protrusions 72a and 72b. Increases the suction force by and facilitates device pick-up.

  The width (maximum width) W2c of the second convex portion 72c shown in FIG. 11C is wider than the width (maximum width) W1 of the first convex portion 71. For this reason, the 2nd convex part 72c becomes a stable support body which supports a device on stage 110 at the time of dicing, and stable dicing becomes possible. Further, at the time of pickup after separation, a wide contact area between the second convex portion 72c and the tip surface 120a of the collet 120 can be secured, and stable pickup is possible.

  The width (maximum width) W2b of the second protrusion 72b shown in FIG. 11B is substantially the same as the width (maximum width) W1 of the first protrusion 71. Furthermore, the pitch between the second convex portion 72 b and the first convex portion 71 adjacent to the second convex portion 72 b is substantially the same as the pitch between the first convex portions 71. That is, the 2nd convex part 72b bears one element of the periodic structure (moth eye structure) with the 1st convex part 71, and has contributed to the improvement of the extraction efficiency of light.

  FIG. 12 is a schematic cross-sectional view showing another example of the uneven structure of the first light transmission layer 31.

  The first light transmission layer 31 shown in FIG. 12 is also provided on the phosphor layer (second light transmission layer) 32 similarly to the above embodiment, and is transmissive to the emitted light of the light emitting layer 13 and the emitted light of the phosphor 32a. Have sex.

  The first light transmission layer 31 has a so-called moth-eye structure in which irregularities are repeated with a period of nm order. That is, the first light transmission layer 31 has a plurality of first protrusions 71e. In the example illustrated in FIG. 12, the first convex portion 71e has, for example, a substantially conical shape. The first light transmission layer 31 formed with such a plurality of first protrusions 71e suppresses reflection of the emitted light of the light emitting layer 13 and the emitted light of the phosphor 32a, and improves the light extraction efficiency of the semiconductor light emitting device. Let

  The first light transmission layer 31 further includes a second protrusion 72e. The 2nd convex part 72e is provided in the outer peripheral side of the semiconductor light-emitting device, for example, is formed in the shape of a line surrounding the area | region in which the some 1st convex part 71e was provided.

  The 1st convex part 71e and the 2nd convex part 72e are integrally provided with the same material. The first light transmission layer 31 including the first convex portion 71e and the second convex portion 72e is made of a material containing, for example, a silicone resin as a main component.

  The binder 32b of the phosphor layer 32 is also made of a material containing, for example, a silicone resin as a main component. However, even with the same silicone resin material, the Young's modulus (first Young's modulus) of the first light transmitting layer 31 is lower than the Young's modulus (second Young's modulus) of the binder 32b of the phosphor layer 32.

  That is, the first light transmission layer 31 containing a material having a first Young's modulus as a main component is more than the binder 32b of the phosphor layer 32 containing a material having a second Young's modulus higher than the first Young's modulus as a main component. Also soft.

  If the second convex portion 72e has a sharp portion, the second convex portion 72e is likely to be chipped at the time of contact with the stage 110 or the collet 120, and the fragments adhere to the device, which may affect the optical characteristics and electrical characteristics of the device.

  The distal end side of the second convex portion 72e shown in FIG. 12 is formed in a curved surface shape having a smaller curvature (larger radius of curvature) than the distal end side of the first convex portion 71e, and has no sharp portion. Therefore, it is possible to suppress the corners of the second protrusions 72e from being lost when contacting the stage 110 or the collet 120. Further, the second convex portion 72e having softness that can be elastically deformed also suppresses breakage.

  The height of the second convex portion 72e is substantially the same as the height of the first convex portion 71e. Here, the “height” represents the height with reference to the upper surface of the phosphor layer (second light transmission layer) 32 underlying the first light transmission layer 31. In addition, the slight difference which arises on manufacture is included substantially the same height.

  Since the height of the first convex portion 71e and the height of the second convex portion 72e are substantially the same, the light extracted from the region where the plurality of first convex portions 71e responsible for the light reflection suppression function is formed is the second. Blocking by the convex portion 72e is suppressed, and the light extraction efficiency of the semiconductor light emitting device is improved.

  13A to 13E are schematic plan views illustrating other examples of the planar layout of the second convex portion of the first light transmission layer 31. FIG.

  The second convex part 72f in FIG. 13A and the second convex part 72g in FIG. 13B have a closed shape in plan view, like the second convex part 72 shown in FIG. doing. Thereby, it is easy to generate a negative pressure at the time of vacuum pickup, and pickup workability is improved.

  The second convex portion does not necessarily have a closed shape in plan view as long as vacuum pickup is possible. Examples of the second protrusions that do not have a closed shape in plan view are shown in FIGS. 13 (c) to 13 (e).

  The second convex portions 72h shown in FIG. 13C are provided on the sides facing each other in the semiconductor light emitting device. Thus, the 2nd convex part 72h may be provided in a plurality of places.

  Similarly, the second convex portions 72i shown in FIG. 13D are provided at two locations so as to face each other. The 2nd convex part 72i is located inside the outer edge part of a semiconductor light-emitting device.

  The second convex portions 72j shown in FIG. 13 (e) are provided at the four corners of the semiconductor light emitting device.

  Next, a specific method for forming the first convex portion 71 and the second convex portion 72 of the first light transmission layer 31 will be described.

  14A to 14C are schematic cross-sectional views illustrating a method for forming a concavo-convex pattern on the first light transmission layer 31 by an imprint method using the template 130. FIG.

  A material layer 131 of the first light transmission layer 31 is formed on the phosphor layer 32. For example, a liquid silicone resin is applied on the phosphor layer 32 as the material layer 131. The template 130 is brought into contact with the liquid material layer 131.

  The template 130 has a concavo-convex pattern including a first recess 130a and a second recess 130b. The uneven pattern of the template 130 is formed using a DSA (directed self-assembly) technique.

  A diblock copolymer, one of the self-organizing materials, is a high molecular compound in which two types of polymers are chemically bonded, and the same polymer components are intermolecularly assembled to cause phase separation in a microscopic region, heat treatment, etc. To form a regular periodic structure. This periodic structure changes to sphere (spherical), cylinder (columnar), or lamella (plate-like) depending on the volume ratio of the polymer component, and the period depends on the molecular weight. Therefore, a fine pattern can be formed by using a diblock copolymer having a specific molecular weight. By selectively removing one polymer component from the microphase-separated structure, a pattern corresponding to a contact hole or a line and space can be formed on the self-organized material.

  The first material and the second material are applied on the pattern forming surface of the template 130. The first material has a first self-organizing characteristic that can be used to form the first recess 130a. The second material has a second self-organizing characteristic that can be used to form the second recess 130b. The second self-organizing characteristic is different from the first self-organizing characteristic.

  For example, BPC (Block Copolymers) forming a spherical domain is applied as the first material. BPC forming an in-plane cylindrical domain is applied as the second material. And each material is phase-separated by heat processing. As a result, a dot-shaped first convex portion is formed in the first region where the first material is applied, and an in-plane cylindrical second convex portion is formed in the second region where the second material is applied.

  By etching the template 130 using the phase-separated first material and second material as a mask, a plurality of first recesses 130 a are formed in the first region of the template 130, and the second region of the template 130 is formed in the second region. A second recess 130b is formed.

  As shown in FIG. 14B, after the concave / convex pattern of the template 130 is brought into contact with the liquid material layer 131, the material layer 131 is cured by light or heat.

  After the material layer 131 is cured, the template 130 is separated from the material layer 131. Thereby, as shown in FIG. 14C, the first convex portion 71 and the second convex portion 72 are simultaneously formed in the first light transmission layer 31.

  At least the second convex portion 72 of the first convex portion 71 and the second convex portion 72 has a Young's modulus lower than that of the binder 32b of the phosphor layer 32 and is soft.

  FIGS. 15A to 15C are schematic cross-sectional views showing a method for forming a concavo-convex pattern in the first light transmission layer 31 by an etching method using the mask 140.

  After the material layer of the first convex portion 71 is formed on the phosphor layer 32, the mask 140 shown in FIG. 15A is formed on the material layer. Then, the lower material layer is etched using the mask 140 to form a plurality of first protrusions 71.

  The mask 140 has a plurality of openings 140a. A DSA technique is used for patterning the mask 140. The mask 140 itself is a material having self-organizing characteristics, and the mask 140 is patterned by phase separation of the material. Alternatively, the mask 140 is patterned by forming a self-organizing material on the mask 140 and etching using the phase-separated self-organizing material as a mask.

  Next, as shown in FIG. 15B, the first convex portion 71 is covered with a mask layer 150, and the material layer 172 of the second convex portion 72 is formed on the phosphor layer 32.

  The material layer 172 is etched back as shown in FIG. At this time, the first convex portion 71 is protected by the mask layer 150. Thereafter, the first convex portion 71 and the second convex portion 72 are formed in the first light transmission layer 31 by removing the mask layer 150.

  At least the second convex portion 72 of the first convex portion 71 and the second convex portion 72 has a Young's modulus lower than that of the binder 32b of the phosphor layer 32 and is soft.

  As described above, by using the DSA technique for forming the concave / convex pattern of the first light transmission layer 31, high-resolution lithography having a molecular level resolution becomes possible, and a fine concave / convex pattern can be obtained at low cost. It can be formed on the one light transmission layer 31.

  FIG. 16 is a schematic cross-sectional view showing another method for forming the second convex portion 72.

  A plurality of first protrusions 71 are formed on the phosphor layer 32 by the method described above, and then the first protrusions 72 are formed by an inkjet method.

  The first convex portion 71 is also formed in a region where the second convex portion 72 is formed. A liquid material is dropped from the nozzle into the region where the first convex portion 71 is formed. Thereafter, the dropped liquid material is cured by heat or light, and the second convex portion 72 is formed. The second convex part 72 is formed so as to rise in a hemispherical shape so as to cover a part of the first convex part 71.

  Due to the surface tension of the liquid material, the distal end side of the second convex portion 72 is formed in a curved surface having a smaller curvature (a larger radius of curvature) than the distal end side of the first convex portion 71, and there is no sharp portion.

  At least the second convex portion 72 of the first convex portion 71 and the second convex portion 72 has a Young's modulus lower than that of the binder 32b of the phosphor layer 32 and is soft.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 13 ... Light emitting layer, 15 ... Semiconductor layer, 16 ... p-side electrode, 17 ... n-side electrode, 21 ... p-side wiring layer, 22 ... n-side wiring layer, 23 ... p-side metal pillar, 24 ... n-side metal pillar, 25 ... resin layer, 31 ... first light transmission layer, 32 ... phosphor layer (second light transmission layer), 32a ... phosphor, 32b ... binding material, 71 ... first projection, 72 ... second projection, 110 ... Stage, 120 ... Collet, 130 ... Template, 140 ... Mask

Claims (6)

A semiconductor layer;
A first light transmission layer having a plurality of first convex portions and a second convex portion having a height equal to or higher than the height of the first convex portion, and containing a material having a first Young's modulus as a main component;
A second light-transmitting layer provided between the semiconductor layer and the first light-transmitting layer and containing as a main component a material having a second Young's modulus higher than the first Young's modulus;
A semiconductor device comprising: A semiconductor layer;
A plurality of first convex portions having a first curvature, and a second convex portion having a second curvature smaller than the first curvature and having a height equal to or higher than the height of the first convex portion. A first light transmission layer;
A semiconductor device comprising:   The semiconductor device according to claim 2, further comprising a second light transmission layer provided between the semiconductor layer and the first light transmission layer.   The semiconductor device according to claim 3, wherein a Young's modulus of the first light transmission layer is lower than a Young's modulus of the second light transmission layer.   The semiconductor device according to claim 1, wherein the second convex portion has a flat region at a top portion. Forming a first light transmission layer having a plurality of first protrusions and a second protrusion having a height equal to or higher than the height of the first protrusions on the semiconductor layer;
A method of manufacturing a semiconductor device, wherein the first convex portion is formed on the first light transmission layer using a pattern transfer body having a pattern formed by self-organization of the first material.

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