JP5246032B2 - Light emitting device and method for manufacturing light emitting device - Google Patents

Description

  The present invention relates to a light emitting device and a method for manufacturing the same, and more particularly to a light emitting device having a light-transmitting film on a substrate surface and a method for manufacturing the same.

  In recent years, a light-emitting device that emits white-color mixed light by combining a light-emitting element formed using a nitride-based compound semiconductor and a phosphor has been developed. In this light emitting device, a part of blue light output from the light emitting element is wavelength-converted by the phosphor, and the wavelength-converted yellow light and blue light from the light emitting element are mixed, It emits white light.

  In order to make the chromaticity of the white light uniform, it is necessary to arrange the phosphors equally on the optical path of the light emitted from the light emitting element. As one of the methods, a technique is known in which a phosphor is electrophoresed in a solution in which a charged phosphor is dispersed. In electrophoresis, a light emitting element and an electrode are placed in a solution and a voltage is applied between them. At this time, the voltage is applied so that a potential opposite to the phosphor band electrode is generated in the light emitting element. For example, the phosphor is attracted to the conductive portion of the light emitting element. By including a binder for adhering the phosphor to the surface of the light-emitting element in the solution, a uniform layer of the phosphor can be formed on the surface of the light-emitting element.

  In the case of a light emitting element having an insulating substrate such as sapphire on the light extraction side, it is necessary to form a conductive layer on the substrate surface in order to deposit the phosphor on the insulating substrate surface. In such an element, since a conductive layer is provided on the light extraction side, it has been proposed to use, for example, a light-transmitting material as the conductive layer (see Patent Documents 1 and 2). In addition, a metal layer such as aluminum having good contact resistance with respect to the nitride compound semiconductor is formed as a conductive layer and dissolved during the deposition of the phosphor, or oxidized and made transparent after the phosphor is deposited. Has also been proposed (see Patent Documents 3 to 7).

JP 2003-69086 A JP 2003-110153 A JP 2008-66365 A JP2007-134378 JP2007-305773 JP2008-300580 JP2007-294728A

  However, when aluminum is used as the material of the conductive layer, there is a problem in that the conductive layer is easily peeled off on the surface in contact with the conveying member such as a collet because the adhesive force with the sapphire substrate is not sufficient. This is not a problem if the peeled area is small enough to be filled with the electrophoresed phosphor, but if transport is repeated using a transport member with a part of the conductive layer attached, the conductive layer is further added to the attached conductive layer. Sticks and the peeled area increases. If the peel-off area of the conductive layer becomes large and a region that is not filled with phosphor is formed, light from the light-emitting element in that region is extracted without being converted by the phosphor, resulting in non-uniform emission distribution and shift in emission wavelength. It leads to.

  A light-emitting element according to a first aspect of the present invention includes a sapphire substrate, a semiconductor layer provided on one main surface of the sapphire substrate, and a translucent film provided on at least the other main surface of the sapphire substrate. The translucent film is an oxide film containing aluminum and contains Cu, Sn, or Zn in an amount of 0.26 mass percent or more and less than 2.10 mass percent.

The light emitting device of the first aspect of the present invention can be combined with the following configurations.
A phosphor layer provided on a surface of the translucent film; The translucent film is also provided on the side surface of the sapphire substrate.

  The method for manufacturing a light emitting device according to the present invention includes a step of forming a semiconductor layer on one main surface of a sapphire substrate, forming an aluminum alloy film on at least the other main surface of the sapphire substrate, and applying a voltage to the aluminum alloy film. A step of depositing a charged phosphor by application, and a step of forming a light-transmitting film by oxidizing the aluminum alloy film, wherein the aluminum alloy film contains Cu, Sn, or Zn. Containing 0.5 mass percent or more and less than 4 mass percent.

The manufacturing method of this invention can combine the following structures.
Before the phosphor deposition step, the method includes a step of transporting the transport support member by adhering it to the surface on which the aluminum alloy film is formed. In the transporting step, the semiconductor substrate is transported on a mounting support substrate, and the semiconductor layer side is flip-chip mounted on the support substrate.

  The light emitting device of the second aspect of the present invention is a sapphire substrate, a semiconductor layer provided on one main surface of the sapphire substrate, and phosphor electrophoresis deposition provided on at least the other main surface of the sapphire substrate. The aluminum alloy film is a film that can be converted to a light-transmitting film by oxidation, and contains Cu, Sn, or Zn by 0.5 mass percent or more and less than 4 mass percent.

  The light-emitting element of the present invention can be a conductive film having excellent adhesion to a sapphire substrate by using an aluminum alloy film containing Cu, Sn, or Zn as a film for phosphor electrophoretic deposition, and can be peeled off from the substrate. Can be suppressed. Further, by oxidizing such an alloy film, a translucent film of an aluminum-containing oxide film containing Cu, Sn, or Zn can be obtained, and a translucent film in which peeling from the substrate is suppressed can be obtained. Light can be extracted from the sapphire substrate side.

FIG. 1 is a schematic cross-sectional view showing a light emitting device according to an embodiment. FIG. 2 is a schematic cross-sectional view illustrating a method for manufacturing a light emitting device according to an embodiment. FIG. 3 is a schematic cross-sectional view illustrating a method for manufacturing a light emitting device according to an embodiment. FIG. 4 is a schematic cross-sectional view illustrating a method for manufacturing a light emitting device according to an embodiment. FIG. 5 is a schematic cross-sectional view illustrating a method for manufacturing a light emitting device according to an embodiment. FIG. 6 is a schematic cross-sectional view illustrating a method for manufacturing a light-emitting element according to an embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the method of the present invention (hereinafter referred to as “embodiments”) will be described in detail with reference to the drawings. In addition, a figure is shown typically, a part is exaggerated and may differ from an actual. The present invention is not limited to the following embodiments and examples, and various modifications can be made without departing from the technical idea of the present invention.

  FIG. 1 is a schematic cross-sectional view showing the light emitting device of this embodiment. As shown in FIG. 1, in the light emitting element 1, a semiconductor layer 14 is provided on one main surface of a sapphire substrate 10, and a translucent film 20 is provided on at least the other main surface of the sapphire substrate 10. . The translucent film 20 is an oxide film containing aluminum, and contains Cu, Sn, or Zn in an amount of 0.26 mass percent or more and less than 2.10 mass percent. As an example, the semiconductor layer 14 includes, from the sapphire substrate 10 side, an n-type semiconductor layer as the first conductivity type layer 11, a light emitting layer 12, and a p-type semiconductor layer as the second conductivity type layer 12. An n electrode is formed as the first electrode 15 in the mold layer 11, and a p electrode is formed as the second electrode 16 in the second conductivity type layer 13. The surface of the light emitting element 1 on the electrode side is covered with an insulating protective film 17 except for the connection portion between the first electrode 15 and the bump of the second electrode 16. The first electrode 15 and the second electrode 16 of the light emitting element 1 are electrically connected to the electrode 32 provided on the surface of the base 31 of the support substrate 30 through the metal bumps 33.

  An example of a method for manufacturing the light emitting device of this embodiment will be described with reference to FIGS. 2-6 is a cross-sectional schematic diagram for demonstrating the main processes of the manufacturing method of this embodiment.

(Aluminum alloy film formation process)
First, as shown in FIG. 2, the light emitting device 1 in which the semiconductor layer 14 is laminated on one main surface of the sapphire substrate is fixed to a fixing member 50 such as an adhesive sheet, and an aluminum alloy is formed on at least the other main surface of the sapphire substrate 10. A film 40 is formed.

  The aluminum alloy film contains a trace amount of Cu, Sn, or Zn. As a result, it is possible to obtain a film whose adhesion is greatly improved and which becomes transparent by oxidation. Specifically, Cu, Sn, or Zn is contained in an amount of 0.5 mass percent or more and less than 4 mass percent. Adhesiveness with a sapphire substrate is improved more than the metal film which consists only of aluminum by setting it as the aluminum alloy film which content of Cu, Sn, or Zn contains 0.5 mass% or more. The adhesion is further improved by setting the content of Cu, Sn, or Zn to 1 mass percent or more, more preferably 2 mass percent or more. When transporting the light emitting element, as shown in FIG. 3, the sapphire substrate side opposite to the surface on which the semiconductor layer 14 is formed is adhered to a transport support member 60 such as a collet to avoid damage to the semiconductor layer. There are many cases. In such a case, if an aluminum alloy film is formed on the surface of the sapphire substrate, the aluminum alloy film 40 is adhered to the transport support member 60 as shown in FIG. By providing the aluminum alloy film 40, peeling of the aluminum alloy film 40 due to adhesion to the conveyance support member 60 can be suppressed. Further, for example, when the light emitting element is sandwiched and transported with tweezers, a problem of peeling may occur in the same manner.

  On the other hand, the aluminum alloy film has a low transmittance to the radiated light from the light emitting element. Therefore, the aluminum alloy film is oxidized in a later-described process to form a light-transmitting film. The transmittance is not improved and it cannot be used as a good translucent film. Therefore, when the content is less than 4 mass percent, a light-transmitting film having high transmittance with respect to light emitted from the light-emitting element can be obtained by oxidation. Moreover, since Sn or Zn tends to decrease the adhesive strength when the content is excessively increased, it is preferably less than 4 mass percent. In addition, it is preferable that the element to be intentionally included is any one of these three elements, and if the element to be included is substantially only aluminum (Al), a light-transmitting film excellent in transmittance by oxidation is formed. Can be obtained. Specifically, the aluminum content is 96 mass percent or more and less than 99.7 mass percent.

  When using an aluminum alloy film as a conductive film for electrophoretic deposition described later, it is preferable to form an aluminum alloy film on the side surface of the substrate. Furthermore, when the aluminum alloy film 40 is provided in contact with the first conductivity type layer 11 as shown in FIG. 2, a voltage can be applied to the aluminum alloy film 40 through the first conductivity type layer 11.

  Examples of the method for forming the aluminum alloy film include vapor deposition, sputtering, screen printing, ink jet coating, spray coating, or a combination thereof. A region where the aluminum alloy film is not desired to be formed, such as the light emitting layer, the second conductivity type layer, and the side surface of the first or second electrode, is covered with a mask material to form the aluminum alloy film. An insulating protective film or resin can be used instead of the mask material. Depending on the film formation conditions, it is difficult to form an aluminum alloy film on the side surface of the element, and the film thickness on the substrate side surface of the aluminum alloy film is smaller than the film thickness on the main surface as in the element shown in FIG. As in the element shown in FIG. 2, by providing a step at the element outer periphery of the first conductivity type layer, the semiconductor layer having the side surface continuous with the substrate side surface can be made only the first conductivity type layer. Under the formation conditions, an aluminum alloy film can be formed from the substrate surface to the side surface of one conductivity type semiconductor layer without requiring a mask material. The first conductivity type layer is preferably covered with an insulating protective film except for the side surface. The film thickness of the aluminum alloy film is about 5 nm to 10 μm, and preferably 20 nm to 1 μm in order to form a relatively homogeneous film. Therefore, it is preferable to set it to 20 nm or more and 300 nm or less. In addition, it is preferable to make the maximum film thickness into these film thickness ranges. For example, the film thickness on the main surface of the sapphire substrate is set in this way, and the film thickness on the side surface of the substrate is set to the same level or smaller.

  The fixing member that fixes the light emitting element is not limited to the adhesive sheet, and any member that can fix the light emitting element may be used. In order to form the aluminum alloy film on the side surface of the sapphire substrate, it is preferable that the light emitting elements are fixed apart from each other. For example, a wafer can be attached to an adhesive sheet, divided into elements, and then expanded to obtain a state as shown in FIG. If an aluminum alloy film is to be formed after being mounted on a package or the like, it is necessary to cover the area other than the region where the aluminum alloy film is to be formed with a mask or the like. Therefore, it is preferable to mount the aluminum alloy film on the package or the like after forming the aluminum alloy film. For example, as shown in FIG. 4, the first electrode 15 and the second electrode 16 of the light emitting element 1 on which the aluminum alloy film 40 is formed are connected to the electrode 32 of the support substrate 30 through the metal bumps 33 on the support substrate 30 side. And fix.

(Phosphor deposition process)
As shown in FIG. 5, the light emitting element 1 is immersed in a solution (electrolytic solution) in the electrodeposition bath. A charged phosphor 81 is dispersed in the solution. Here, since each electrode of the light emitting element 1 is electrically connected to the electrode 32 of the support substrate 30, a counter electrode 70 is installed so as to face the electrode 32 of the support substrate 30, and the electrode 32 and the counter electrode are externally powered. A voltage is applied during 70. At this time, by applying a voltage having a polarity different from the charging of the phosphor 81 to the electrode 32, a voltage is also applied to the light emitting element 1, and the phosphor 81 in the solution migrates toward the light emitting element 1. Since the portion of the conductive aluminum alloy film 40 in the surface of the light emitting element 1 is charged with the opposite polarity to the phosphor 81, the phosphor 81 is deposited on the surface with a uniform film thickness. If the excess solvent contained in the deposit is removed by drying the deposit, a phosphor layer 80 containing the phosphor as shown in FIG. 6 can be formed with a substantially uniform film thickness.

  The light emitting element may be arranged so that at least the aluminum alloy film can be charged to a polarity different from that of the phosphor. As shown in FIG. 4, if the light emitting element 1 having the aluminum alloy film 40 in contact with the semiconductor layer 14 is mounted on the support substrate 30 before the phosphor deposition step, a voltage is applied to the electrode 32 of the support substrate 30. Is applied, the aluminum alloy film 40 can be charged with a polarity different from that of the phosphor in the solution. When the light emitting element with the aluminum alloy film exposed is flip-chip mounted, for example, as shown in FIG. 3, the aluminum alloy film 40 is transported by being adhered to the transport support member 60 and bonded to the support substrate. In this case, since a high load is applied to the aluminum alloy film in contact with the conveying support member, the adhesion between the sapphire substrate and the aluminum alloy film is particularly important. As a means used for such joining, there is, for example, ultrasonic joining.

  The solution used for the electrophoretic deposition may contain a binder or a charging material in addition to the phosphor. In this case, the formed phosphor layer includes a binder and a charging material in addition to the phosphor. Furthermore, the phosphor layer may have a translucent resin that covers the phosphor and the binder. In addition, the phosphor is charged before the step of applying a voltage by the phosphor itself is charged or by other chargeable materials contained in the electrolytic solution, such as a polar translucent material. Good.

(Aluminum alloy film oxidation process)
By oxidizing the aluminum alloy film, a light-transmitting film of an aluminum oxide film containing a small amount of Cu, Sn, or Zn can be obtained. When the phosphor is electrophoretically deposited by charging the aluminum alloy film, the translucent film 20 is positioned between the sapphire substrate 10 and the phosphor layer 80 as shown in FIG. As a method for oxidizing the aluminum alloy film, a heat treatment method in an oxidizing atmosphere, for example, a water vapor atmosphere can be used. Specifically, heating is performed under conditions containing high-temperature steam, for example, heating is performed under conditions of high temperature and high humidity such as a temperature of 130 ° C. or higher and a humidity of 100% or higher. As a result, the aluminum alloy film is modified to a translucent film and further to an insulating film.

  The content of Cu, Sn or Zn in the translucent film is preferably 0.26 mass percent or more and less than 2.10 mass percent, and more preferably 0.52 mass percent or more and 1.06 mass percent or more. It is preferable to do. The content of Cu in the translucent film obtained by oxidation is about 0.26 mass percent when 0.5 mass percent of Cu is contained in the aluminum alloy film, and 0.52 when 1 mass percent is contained. It is estimated that about 1.06 mass percent when it is contained in about 2 mass percent, about 2.10 mass percent when it is contained in 4 mass percent, and about the same in the case of Sn or Zn It is estimated to be. The element intentionally included in the Al-containing oxide film that is a light-transmitting film is preferably Cu, Sn, or Zn. In this case, the Al content in the light-transmitting film is 50 to 52. It is estimated to be about mass percent. The film thickness of the translucent film is not particularly limited, but the film thickness is about 5 nm to 10 μm. Specifically, as the translucent coating film, the film thickness is about 20 nm or more and 1 μm or less in order to form a relatively homogeneous film. To the extent.

  Furthermore, you may provide the process of forming the translucent member of translucent materials, such as resin, in a fluorescent substance layer. Specifically, a light-emitting element provided with a phosphor layer is arranged, and a light-transmitting material is applied on the phosphor layer, or the element is immersed in a solution containing the light-transmitting material, A coating film for the translucent member is formed.

  When the phosphor deposition step is omitted, the light-emitting element 1 in which the light-transmitting film 20 is provided on the light extraction side surface of the sapphire substrate 10 as shown in FIG. 1 can be obtained. Since a light-transmitting film obtained by oxidation of an aluminum alloy film tends to have a lower strength than an aluminum alloy film, a light emitting element provided with an aluminum alloy film is first formed even when the phosphor deposition process is not performed. It is preferable to perform an oxidation process after mounting the light-emitting element to obtain a light-emitting element having a light-transmitting film on the surface of the sapphire substrate. With such a light emitting element, peeling of the aluminum alloy film at the time of flip chip mounting can be suppressed, so that the surface of the sapphire substrate can be uniformly covered with the light transmitting film. Further, the light-transmitting film obtained by oxidation of the aluminum alloy film tends to have irregularities on the surface, and light from the inside of the light emitting element can be suitably extracted by reflection on the irregular surface.

  Each member concerning this embodiment is explained in full detail below.

(Light emitting element 1)
An LED chip will be described as the light emitting element 1 in the present embodiment. Examples of the light emitting element constituting the LED chip include semiconductor light emitting elements formed of various semiconductors. A semiconductor that can be grown on a sapphire substrate can be selected, and a nitride semiconductor (In _X Al _Y Ga) can be selected. _1-X—Y N, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) are preferable. Nitride semiconductors are preferred when using phosphors because they can emit light at short wavelengths that can excite phosphors efficiently. Various emission wavelengths can be selected depending on the semiconductor material and the degree of mixed crystal. Specifically, as shown in FIGS. 1 to 6, semiconductor layers 14 of different conductivity types (first conductivity) are provided on one main surface side of the sapphire substrate 10 via a base layer that can be omitted by a growth method. A structure in which a semiconductor structure having a light-emitting structure is provided by stacking an n-type semiconductor layer as a mold layer 11 and a p-type semiconductor layer as a second conductivity type layer 13) and a light-emitting layer 12 in the order of reference numerals from the substrate side. Can be used. Note that the stacking order need not be this.

(Supporting substrate 30)
The base substrate material for mounting the light emitting element is preferably AlN, Al ₂ O ₃ , SiC, GaAs, BN, C (diamond), or the like. More preferably, aluminum nitride (AlN) is selected for a light-emitting element having a thermal expansion coefficient substantially equal to that of the light-emitting element, for example, a light-emitting element made of a nitride-based semiconductor. Thereby, the influence of the thermal stress which generate | occur | produces between a support body and a light emitting element can be relieve | moderated.

(Phosphor 81, phosphor layer 80)
The phosphor is a phosphor that emits light having different wavelengths by absorbing at least a part of light from the light emitting element, and the phosphor layer is a member containing the phosphor. The phosphor layer is preferably composed of a phosphor, and may additionally have a binder for fixing the phosphor. In addition, in order to strengthen the fixation of the phosphor layer to the light emitting element or device, or to protect it from the external environment, the phosphor layer formed by electrophoretic deposition is composed of a translucent member, a sealing member, as described above. As a material such as a member, a structure covered with another light-transmitting material such as a light-transmitting resin such as epoxy resin or silicon resin, or glass is preferable.

  The phosphor converts light from the light emitting element, and it is more efficient to convert light from the light emitting element to a longer wavelength. When the light from the light emitting device is high-energy short-wavelength visible light, an yttrium-aluminum-garnet-based phosphor (YAG: Ce) activated with cerium, which is a kind of aluminum oxide-based phosphor, is preferably used. It is done. In particular, the YAG: Ce phosphor absorbs part of the blue light from the LED chip depending on its content and emits yellow light that is a complementary color. Can be formed relatively easily.

  The phosphor in the present embodiment preferably has a shape and size that facilitates electrophoresis in the electrolytic solution. In particular, for electrophoresis in an electrolytic solution, it is preferable that the phosphor has a substantially spherical particle shape. Since a phosphor having a large particle size of about 15 μm is difficult to deposit, the average particle size of the phosphor can be about 3 to 10 μm. Further, charging of the particle surface and the particle coating film can also be utilized by surface treatment such as providing a surface coating film on the surface of the phosphor particles. A fluorescent substance layer shall be more than the particle size of fluorescent substance particle, for example, shall be about 0.1-10 micrometers in film thickness. As shown in FIG. 5, when the aluminum alloy film 40 is charged using the electrode 32 of the support substrate 30 and electrophoretic deposition is performed, the phosphor layer 80 is also formed on the electrode 32 of the support substrate 30. In some cases, the phosphor 81 also enters between the electrode 32 of the support substrate 30 and the light emitting element 1 to form the phosphor layer 80. At this time, if the light emitting element has a step in the outer peripheral portion of the first conductivity type layer 14, the phosphor layer 80 tends to be formed along the step, and the penetration of the phosphor 81 into the element is suppressed. can do.

  The light-emitting element of this example includes a semiconductor layer provided on one main surface of a sapphire substrate, and a light-transmitting oxide film containing Al and Cu provided on the other main surface and side surfaces of the sapphire substrate. Prepare. The light emitting device according to this example is manufactured as follows.

  First, a semiconductor layer made of a gallium nitride compound semiconductor is stacked on one main surface of a sapphire substrate. In the semiconductor layer, an n-type semiconductor layer, a light emitting layer, and a p-type semiconductor layer are stacked in this order from the substrate side. On the surface of the p-type semiconductor layer, a full-surface electrode that reflects light from the light emitting layer and a pad electrode that covers it are formed as a p-electrode, and an n-electrode is exposed on the surface of the n-type semiconductor layer exposed from the p-type semiconductor layer. Form. As the material of each electrode, the p-side full surface electrode contains Ag, the pad electrode contains Ni and Au, and the n electrode contains Al—Si—Cu alloy and W, respectively. As a protective film, a Si oxide film is formed to cover the surface of each electrode and semiconductor layer. Note that the side surface of the n-type semiconductor layer continuous from the substrate and the connection portion between each electrode and the bump are not covered with a protective film.

  Next, the n-electrode and p-electrode sides of the light-emitting element are attached to an adhesive sheet, and an aluminum alloy film containing about 1 mass percent Cu and about 99 mass percent Al is sputtered onto the other main surface and side surfaces of the sapphire substrate. It is formed with a film thickness of 75 nm. The aluminum alloy film is formed up to the side surface of the n-type semiconductor layer exposed from the protective film. The aluminum alloy film on the side surface has a thickness smaller than that of the main surface, and is about 7 to 10 nm. When the adhesive strength of the aluminum alloy film thus formed is measured by a scratch test, no peeling is seen in the aluminum alloy film.

  Such a light-emitting element is flip-chip mounted on a support substrate. The other main surface side of the sapphire substrate on which the aluminum alloy film is formed is adsorbed to the collet to transport the light emitting element, and the electrode of the support substrate and the electrode of the light emitting element are ultrasonically bonded via the Au bump. Next, a support substrate on which the light emitting element is mounted is placed in the electrolytic solution, and a voltage is applied to the aluminum alloy film, whereby an yttrium, aluminum, garnet phosphor having an average particle diameter of 5 μm is formed on the light emitting element. Electrophoretic deposition. The applied voltage is 50 to 60 V and the electrophoresis time is 7 minutes. Thereby, a phosphor layer having a film thickness of about 15 to 25 μm is obtained on the light emitting element.

  The support substrate is taken out from the electrolytic solution, and the aluminum alloy film is made translucent under high temperature steam. That is, the aluminum alloy film is oxidized and converted into a light-transmitting oxide by leaving the supporting substrate on which the light-emitting element is mounted for 6 hours under conditions of 130 ° C. and 100% humidity in the reaction furnace. . The oxide thus obtained is estimated to contain about 0.52 weight percent Cu and about 51.6 weight percent Al. The light emitting element on which the phosphor layer is formed is covered with a translucent member made of silicon resin.

(Comparative Example 1)
A light emitting device of Comparative Example 1 different from Example 1 in that the aluminum alloy film is a metal film made of aluminum is manufactured. When the adhesion force is measured by a scratch test, the aluminum film of Comparative Example 1 is peeled off. Further, the aluminum alloy film of Example 1 has stronger adhesion to the sapphire substrate than the aluminum film of Comparative Example 1, and the area to be peeled off when flip chip mounting is carried by a collet is smaller in Example 1 and peeled off. It can be confirmed that it is difficult. When observed after flip chip mounting, the light-emitting element of Comparative Example 1 has a hole with a diameter of 100 μm or more formed by peeling off the aluminum film. When observed after the phosphor is deposited, the phosphor is attached to the hole. Absent. When the aluminum alloy film and the aluminum film are observed after oxidation, the oxide film of Example 1 tends to be closer to the flat surface than the oxide film of Comparative Example 1.

(Comparative Examples 2 and 3)
The light emitting elements of Comparative Examples 2 and 3 different from Example 1 in that the Cu contained in the aluminum alloy film is about 0.2 mass percent and about 0.33 mass percent are manufactured. The adhesion of the aluminum alloy films of Comparative Examples 2 and 3 to the sapphire substrate is almost the same as that of the aluminum film of Comparative Example 1, and the aluminum alloy film of Example 1 is more sapphire than the aluminum alloy films of Comparative Examples 2 and 3. It has a strong adhesion to the surface and is difficult to be peeled off when flip chip mounting is carried by a collet.

(Comparative Example 4)
The light emitting element of Comparative Example 4 which is different from Example 1 in that Cu contained in the aluminum alloy film is about 4 mass percent is manufactured. In the light emitting device of Comparative Example 4, the oxide film obtained by oxidizing the aluminum alloy film under the same conditions as in Example 1 after electrophoretic deposition of the phosphor has a transmittance for blue light emitted from the light emitting device. It is much lower than Examples 1 and 2, and does not provide a sufficiently light-transmitting film. The oxide of the light emitting device of Comparative Example 4 is estimated to contain about 2.1 mass percent Cu and about 50 mass percent Al.

  A light emitting device of Example 2 which is different from Example 1 in that Cu contained in the aluminum alloy film is about 0.5 mass percent is manufactured. The aluminum alloy film of Example 2 becomes a light-transmitting oxide film by being oxidized under the same conditions as in Example 1. When the scratch test is performed on the aluminum alloy film of Example 2, peeling is less than the aluminum film of Comparative Example 1 and the aluminum alloy films of Comparative Examples 2 and 3. The aluminum alloy film of Example 2 has stronger adhesion to the sapphire substrate than the aluminum films or aluminum alloy films of Comparative Examples 1 to 3, and is difficult to peel off when transported by a collet and mounted on a flip chip. The oxide of the light emitting device of this example is estimated to contain about 0.26 mass percent Cu. In addition, when a scratch test is performed on the aluminum alloy films of Example 1 and Example 2 and compared, Example 1 is less peeled than Example 2.

  The light emitting element of Example 3 which is different from Example 1 in that the Cu contained in the aluminum alloy film is about 2 mass percent is manufactured. The aluminum alloy film of Example 3 becomes a light-transmitting oxide film by being oxidized under the same conditions as in Example 1. When the scratch test is performed on the aluminum alloy film of Example 3, peeling is less than that of the aluminum films or aluminum alloy films of Comparative Examples 1 to 3. The aluminum alloy film of Example 3 has stronger adhesion to the sapphire substrate than the aluminum films or aluminum alloy films of Comparative Examples 1 to 3, and is difficult to peel off when transported by a collet and flip-chip mounted. The oxide of the light emitting device of this example is estimated to contain about 1.06 mass percent Cu. In addition, when a scratch test is performed on the aluminum alloy films of Examples 1 to 3 and compared, Example 3 has the least peeling.

  When the aluminum alloy film is formed, the light emitting device of Example 4 which is different from Example 1 in that Sn is contained in an amount of about 0.5 mass percent instead of Cu is manufactured. The aluminum alloy film of Example 4 becomes a light-transmitting oxide film by being oxidized under the same conditions as in Example 1, and has stronger adhesion to the sapphire substrate than the aluminum film of Comparative Example 1. It is estimated that Sn contained in the oxide of the light emitting element of this example is about 0.26 mass percent.

(Comparative Example 5)
The light emitting element of Comparative Example 5 which is different from Example 4 in that Sn contained in the aluminum alloy film is about 4 mass percent is manufactured. The aluminum alloy film of Example 4 has stronger adhesion to the sapphire substrate than the aluminum alloy film of Comparative Example 5, and is difficult to peel off when transported by a collet and mounted on a flip chip. Note that the oxide of the light-emitting element of Comparative Example 5 is estimated to contain about 2.1 mass percent of Sn.

  When forming the aluminum alloy film, the light emitting device of Example 5 which is different from Example 1 in that Zn is contained in an amount of about 0.5 mass percent instead of Cu is manufactured. The aluminum alloy film of Example 5 becomes a light-transmitting oxide film when oxidized under the same conditions as in Example 1, and has stronger adhesion to the sapphire substrate than the aluminum film of Comparative Example 1. Zn contained in the oxide of the light emitting device of this example is estimated to be about 0.26 mass percent.

(Comparative Example 6)
A light emitting device of Comparative Example 6 which is different from Example 5 in that Zn contained in the aluminum alloy film is about 4 mass percent is manufactured. The aluminum alloy film of Example 5 has stronger adhesion to the sapphire substrate than the aluminum alloy film of Comparative Example 6, and is difficult to peel off when transported by a collet and mounted on a flip chip. The oxide of the light emitting device of Comparative Example 6 is estimated to contain about 2.1 mass percent of Zn.

DESCRIPTION OF SYMBOLS 1 Light emitting element 10 Sapphire substrate 11 1st conductivity type layer, 12 Light emitting layer, 13 2nd conductivity type layer, 14 Semiconductor layer 15 1st electrode, 16 2nd electrode 17 Protective film 20 Translucent film 30 Support substrate, 31 Base , 32 Support substrate side electrode 40 Aluminum alloy film 50 Fixing member 60 Support member for conveyance 70 Counter electrode 80 Phosphor layer, 81 Phosphor

Claims (7)

A sapphire substrate,
A semiconductor layer provided on one main surface of the sapphire substrate;
A translucent film provided on at least the other main surface of the sapphire substrate,
The translucent film is an oxide film containing aluminum, and contains 0.26 mass percent or more and less than 2.10 mass percent of Cu, Sn, or Zn.   The light emitting element of Claim 1 which has the fluorescent substance layer provided in the surface of the said translucent film | membrane.   The light-emitting element according to claim 1, wherein the translucent film is also provided on a side surface of the sapphire substrate. Forming a semiconductor layer on one main surface of the sapphire substrate and forming an aluminum alloy film on at least the other main surface of the sapphire substrate;
Depositing a charged phosphor by applying a voltage to the aluminum alloy film;
Oxidizing the aluminum alloy film to form a light-transmitting film,
The said aluminum alloy film is a manufacturing method of the light emitting element which contains Cu, Sn, or Zn 0.5 mass percent or more and less than 4 mass percent.   The method for manufacturing a light-emitting element according to claim 4, further comprising a step of adhering and conveying a conveyance support member to the surface on which the aluminum alloy film is formed before the phosphor deposition step.   The method for manufacturing a light emitting element according to claim 5, wherein in the transporting step, the semiconductor substrate is transported on a mounting support substrate, and the semiconductor layer side is flip-chip mounted on the support substrate. A sapphire substrate,
A semiconductor layer provided on one main surface of the sapphire substrate;
An aluminum alloy film for phosphor electrophoresis deposition provided on at least the other main surface of the sapphire substrate,
The aluminum alloy film is a film that can be converted to a light-transmitting film by oxidation, and contains 0.5 mass percent or more and less than 4 mass percent of Cu, Sn, or Zn.

Images