JP2007134602A - Surface mount semiconductor light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface mount semiconductor light emitting device with a semiconductor light emitting element mounted on an electrode pattern by a eutectic bonding free of the influence of a high heat even placed in the high temperature environment at the time of the eutectic bonding, capale of sustaining a high light emitting efficiency and a high light taking-out efficiency even though it is exposed under the light environment of the high temperature high-humidity environment and a short wavelength region for a long-term use, and having a high degree of mounting freedom. <P>SOLUTION: The electrode pattern and an external-circuit-connection electrode connected with an external electrode to introduce a power sterically formed on a part of the electrode pattern are provided on an Si base material obtained with the Si wafer processed, and the semiconductor light emitting element eutectic bonded on the electrode pattern and an overhead-wired bonding wire are plastic molded by the sealing resin. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a surface mount semiconductor light emitting device in which a mounting surface and an electrode connection surface are the same surface with respect to a motherboard to be mounted.

  For example, there are semiconductor light emitting devices of the type in which a semiconductor light emitting element is mounted on a package obtained by insert molding of a lead frame with a resin as shown in FIGS. 12 is a plan view, and FIG. 13 is a cross-sectional view taken along line AA of FIG. That is, a pair of plate-like lead frames 50a and 50b is insert-molded with a light-reflective resin to form a package of the semiconductor light-emitting device 51, and a bowl-shaped recess 54 having an opening 53 is formed in the lamp house 52 of the package. Is provided. The lead frames 50a and 50b have a base material of Cu, and are Ag-plated after being insert-molded.

  One end portions 55a and 55b of the lead frames 50a and 50b are exposed on the inner bottom surface of the recess 54 so as to face each other, and AuSn eutectic is used as a lower electrode on the exposed lead frame 55a. The LED chip 56 provided with an alloy is die-bonded by eutectic bonding so that the lower electrode of the LED chip 56 and the lead frame 55a are electrically connected. On the other hand, the upper Au electrode of the LED chip 56 is connected to the other lead frame 55b exposed on the inner bottom surface of the recess 54 through the bonding wire 57, and the upper electrode of the LED chip 56 and the lead frame 55b are electrically connected. It is illustrated.

  Further, the recess is filled with a translucent sealing resin 58, and the LED chip 56 and the bonding wire 57 are resin-sealed.

  The other end portions 59a and 59b of the lead frames 50a and 50b, each having one end portion 55a and 55b exposed at the inner bottom surface of the concave portion of the lamp house 52, project outward from the opposite side surface 60 of the lamp house 52. In the vicinity of the protruding portion, the light is bent at a substantially right angle along the side surface 60 of the lamp house 52, and is bent at a substantially right angle again through the side surface 60 side, and wraps around the bottom surface 61 side (see, for example, Patent Document 1).

  In this case, the fluorescent material is mixed in the sealing resin 58 that seals the LED chip 56, the fluorescent material is excited by a part of the light emitted from the LED chip 56, the wavelength is converted, and the light is emitted from the LED chip 56. A semiconductor light emitting device 51 that emits light of a color tone different from that of light can be realized.

  For example, when the light emitted from the LED chip is blue light, one of the blue light emitted from the LED chip is mixed by mixing a fluorescent material that is excited by the blue light and converts the wavelength into yellow light that is a complementary color of blue. White light can be produced by additive color mixing of yellow light wavelength-converted by exciting the fluorescent material and blue light emitted from the LED chip.

  Similarly, when the light emitted from the LED chip is blue light, it is emitted from the LED chip by mixing two phosphor materials that are excited by the blue light and wavelength-converted into green light and red light, respectively. It is also possible to produce white light by additive color mixing of green light and red light that have been wavelength-converted by exciting a fluorescent material with part of the blue light, and blue light emitted from the LED chip.

  In addition, when the light emitted from the LED chip is ultraviolet light, it is emitted from the LED chip by mixing three kinds of fluorescent materials that are excited by the ultraviolet light and respectively convert the wavelength into blue light, green light, and red light. It is also possible to produce white light by additive color mixing of blue light, green light, and red light, which is wavelength-converted by exciting a fluorescent material with a part of the ultraviolet light.

  Furthermore, light of various colors other than white light can be created by appropriately combining the wavelength of light emitted from the LED chip and at least one or more types of fluorescent materials mixed in the sealing resin.

In addition, a general manufacturing process of such a type of semiconductor light emitting device is such that LED chips are placed in each of a plurality of lamp houses obtained by insert-molding a large number of lead frames with resin, and bonding wires are formed. After aerial wiring and sealing them with resin, the lead frame tie bar part is cut and separated into individual semiconductor light emitting devices, and the lead frame that protrudes from the lamp house and becomes the solder joint terminal part is formed into a desired shape. To complete.
JP 2003-7946 A

  By the way, when an LED chip is mounted on a lead frame insert-molded with resin, the eutectic alloy of AuSn provided on the lower electrode of the LED chip is eutectic bonded to the lead frame via solder. Is done. At that time, heat of 300 ° C. or more is applied to the package of the semiconductor light emitting device, and the resin forming the lamp house of the package is required to be able to withstand even under such a high temperature environment. In addition to various molding conditions (for example, molding temperature and molding pressure), durability against a special mounting temperature environment is required.

  Resins that can withstand such special mounting temperature environments include engineering plastics such as LCP (liquid crystal polymer) and PEEK (polyether ether ketone), but the visible light region required for the lamp house where the LED chip is mounted. PPA (polyphthalamide), nylon 9T, and the like that satisfy the high light reflectivity at 1 are difficult to use because the eutectic bonding temperature exceeds the heat distortion temperature.

  Therefore, it is conceivable that a filler is mixed into the resin in order to increase the heat-resistant temperature. However, mixing the filler decreases the light reflectivity and decreases the fluidity. Therefore, adjustment of molding conditions such as molding temperature, injection speed and injection pressure is more difficult than ordinary resins, and there is a problem in using it for a surface mount semiconductor device which is small and requires thin molding.

In a high-temperature and high-humidity environment, photooxidation and thermal oxidation of TiO ₂ inorganic particles constituting the filler are accelerated. As a result, the decrease in light reflectance is promoted, the light extraction efficiency is lowered, and the light intensity of the semiconductor light emitting device rapidly decreases.

  Furthermore, the irradiance and photon energy received by the resin that forms the lamp house are higher than ever, due to the reduction in size and thickness of semiconductor light-emitting devices, higher output of LED chips mounted on semiconductor light-emitting devices, and shorter wavelengths of emitted light. The light reflectance decreases due to the light deterioration of the lamp house.

  Then, the rate of change of light intensity with time differs between a semiconductor light emitting device in which an LED chip that emits light in the short wavelength region is mounted in the same package and a semiconductor light emitting device in which an LED chip that emits light in the long wavelength region is mounted. As the cumulative lighting time becomes longer, the light intensity difference between the two gradually increases.

  In addition, the sealing resin that seals the LED chip and the bonding wire has a role of protecting the LED chip from the external environment such as moisture, dust, and gas, and protecting the bonding wire from mechanical stress such as vibration and impact. In addition, by forming an interface with the light emitting surface of the LED chip, it also has a function of efficiently emitting light emitted from the LED chip from the light emitting surface of the LED chip into the sealing resin.

  Furthermore, the sealing resin that seals the LED chip that emits light in the ultraviolet to visible to infrared wavelength region has a transmittance over the ultraviolet to visible to infrared wavelength region so as not to cause light guiding loss. In particular, it is not included in the light irradiated from the outside such as sunlight and illumination light, especially due to the heat generated by self-heating when the LED chip is turned on and the light in the short wavelength region included in the emitted light. There is a requirement that the transmittance does not decrease due to light in the short wavelength region.

  Therefore, if silicone resin or modified silicone-epoxy resin with good light resistance to light in the short wavelength region is used as the sealing resin, it will peel off at the interface formed between the lamp house and the sealing resin due to deterioration of the lamp house. This interfacial delamination forms a moisture absorption path with the outside (atmosphere) of the semiconductor light emitting device, thereby causing oxidation and sulfurization of the Ag plating applied to the lead frame. Oxidation and sulfidation of the lead frame causes a decrease in reflectance, lowers the reflectance of light emitted from the LED chip, lowers light extraction efficiency, and causes a decrease in luminous intensity of the semiconductor light emitting device.

  This also reduces the adhesion between the lamp house and the lead frame, and includes the problems of moisture resistance of the semiconductor light emitting device and reflow resistance when the semiconductor light emitting device is mounted.

  By the way, the surface-mount type semiconductor light-emitting device includes a so-called top-view type surface-mount type semiconductor light-emitting device in which the optical axis is mounted substantially perpendicular to the mounting surface when mounted on the motherboard, and the optical axis. There is a type called a side-view type surface-mount type semiconductor light-emitting device that is mounted so as to be substantially parallel to the mounting surface. In a semiconductor light emitting device that mounts semiconductor light emitting elements on a package obtained by insert molding of the lead frame with resin, both top view and side view types are mounted in the same package for lead frame forming processing. It is impossible to combine methods.

  Some top-view type surface-mount semiconductor light-emitting devices configured with a rigid substrate instead of a lead frame are mounted on a motherboard by a side-view type mounting method. In this case, a general manufacturing process of a top-view type surface-mount semiconductor light-emitting device is connected to a plurality of LED chips placed at a predetermined interval on a rigid multi-sided substrate and an upper electrode of each LED chip. In order to cover a plurality of bonding wires wired overhead, the resin is integrally sealed with a sealing resin and separated into individual semiconductor light emitting devices by dicing cutting at predetermined intervals.

  When a top-view type surface-mount semiconductor light-emitting device manufactured through such a manufacturing process is mounted on a motherboard by a side-view type mounting method, a circuit pattern formed on the motherboard and an electrode pattern formed on the semiconductor light-emitting device Each of the surfaces does not become substantially parallel to each other. Therefore, at the time of solder joining, one of the semiconductor light emitting devices rises from the motherboard simultaneously with the melting of the solder, so-called Manhattan phenomenon (Tombstone phenomenon), the solder pattern is melted and the solder becomes the electrode pattern of the semiconductor light emitting device. As a result, solder defects such as a so-called wicking phenomenon in which solder does not exist at the contact portion between the electrode pattern of the semiconductor light emitting device and the circuit pattern of the mother board occur, leading to deterioration of the quality of the mother board.

  Therefore, the present invention was devised in view of the above problems, and its object is to eliminate the thermal influence when the semiconductor light-emitting element is eutectic bonded to the substrate, and has good heat dissipation and lighting. Change in optical characteristics over time over a long period of time by suppressing a decrease in light emission efficiency due to self-heating of the light and suppressing a decrease in light extraction efficiency in a high-temperature, high-humidity environment and in a short-wavelength light environment The present invention provides a semiconductor light emitting device and a method for manufacturing the same that can be used for both a top-view type and a side-view type mounting method for a mother board and can ensure reliable mounting. is there.

  In order to solve the above problems, the invention described in claim 1 of the present invention is such that an electrode pattern separated into a plurality through an insulating layer is formed on the surface of a Si substrate on which a recess having an opening is formed, At least two of the electrode patterns are provided with an external circuit connection electrode on at least one place, and a semiconductor light emitting element is mounted by eutectic bonding on the electrode pattern disposed on the inner bottom surface of the recess to form a bonding wire The semiconductor light emitting element and the bonding wire are sealed with a resin by filling the recess with a sealing resin.

  According to a second aspect of the present invention, in the first aspect, the external circuit connection electrode is three-dimensionally formed, and when the surface-mount type semiconductor light emitting device is mounted on the mother board, the mother board is mounted on the mother board. It has a surface that is substantially parallel to the surface of the surface-mounted semiconductor light-emitting device that faces the surface-mounted semiconductor light-emitting device.

  Moreover, the invention described in claim 3 of the present invention is that, in any one of claims 1 and 2, the sealing resin is such that at least one fluorescent substance is mixed in the translucent resin. It is a feature.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the optical axis is substantially perpendicular to the mother board on which the surface mount semiconductor light emitting device is mounted. Both the mounting method that faces the direction and the mounting method that the optical axis faces the direction substantially parallel to the mother board are possible.

  Further, in the invention described in claim 5 of the present invention, an electrode pattern separated into a plurality through an insulating layer is formed on the surface of the Si base formed on the side where two concave portions having openings are opposed to each other, At least four of the electrode patterns are provided with an external circuit connection electrode on at least one place, and a semiconductor light emitting element is mounted by eutectic bonding on the electrode pattern arranged on the bottom surface of each of the recesses. The semiconductor light emitting element and the bonding wire are resin-sealed by aerial wiring via bonding wires and filled with a sealing resin in the respective recesses.

  According to a sixth aspect of the present invention, in the fifth aspect, the external circuit connection electrode is three-dimensionally formed, and the surface-mounted semiconductor light-emitting device is mounted on the motherboard when mounted on the motherboard. It has a surface that is substantially parallel to the surface of the surface-mounted semiconductor light-emitting device that faces the surface-mounted semiconductor light-emitting device.

  Moreover, the invention described in claim 7 of the present invention is that, in any one of claims 5 and 6, the sealing resin is such that at least one fluorescent substance is mixed in the translucent resin. It is a feature.

  According to an eighth aspect of the present invention, in any one of the fifth to seventh aspects, an optical axis is substantially parallel to the mother board on which the surface-mount type semiconductor light emitting device is mounted. And a mounting method in which the light emitting directions of the semiconductor light emitting elements mounted in the two concave portions are directed in opposite directions to each other.

  In the present invention, a plurality of electrode patterns separated through an insulating layer are formed on the surface of a Si base material having a recess having an opening, and external circuit connection electrodes are partially provided on the electrode pattern, A semiconductor light emitting device is mounted by eutectic bonding on the electrode pattern disposed on the bottom surface of the recess and is wired overhead via a bonding wire. The recess is filled with a sealing resin, and the semiconductor light emitting device and the bonding wire are made of resin. It is sealed.

  Therefore, it is not affected by high heat even in a high temperature environment when a semiconductor light emitting device is mounted on an electrode pattern by eutectic bonding. Thus, a surface-mount type semiconductor light-emitting device that can maintain high light emission efficiency and high light extraction efficiency even when exposed to the light environment, and has a high degree of freedom in mounting has been realized.

  Even when the semiconductor light-emitting element is placed on the electrode pattern by eutectic bonding, it is not affected by high heat, and light in a high-temperature and high-humidity environment and in a short wavelength region over a long period of use. A semiconductor light emitting element is eutectic-bonded on an Si base electrode formed by processing a Si wafer and forming an electrode on the surface, with the aim of maintaining high light emission efficiency and high light extraction efficiency even when exposed to the environment. And realized.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 8 (the same portions are given the same reference numerals). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  1 to 3 are diagrams showing a first embodiment of a surface-mount type semiconductor light emitting device according to the present invention, FIG. 1 is a perspective view showing from the front side, and FIG. 2 is a perspective view showing from the back side. 3 is a cross-sectional view taken along the line AA of FIG.

  A concave portion 4 having an opening 3 is provided in a substantially central portion of the first side surface 2 of the substantially square pillar-shaped Si base material 1. The shape of the recess 4 is a shape having an inner peripheral surface 6 that opens outward from the rectangular inner bottom surface 5 of the recess 4 toward the rectangular opening 3, but is not necessarily limited to this shape. .

  Further, the Si base material 1 is penetrated from the first side surface 2 to the first side surface 2 substantially perpendicularly to each of the opening edge portions 7 of the opposing recesses 4 and the end surface edge portion 8 of the Si base material 1. A through hole 9 is provided. The through-hole 9 has a substantially rectangular cross section cut by a plane perpendicular to the depth direction, but is not necessarily limited to this shape.

  Further, the four sides (ridges) 10 having a substantially quadrangular prism shape are formed in a shape that is cut halfway inward from the opposing end surfaces 11. The above is the overall shape of the Si base material as a base. Next, the electrode pattern provided on the Si substrate will be described. First, an oxide film 20 is formed on the entire surface of the Si base 1 processed into the above-described shape, and all electrode patterns described below are formed on the oxide film 20 serving as an insulating layer.

  A pair of separated electrode patterns 12 a and 12 b are formed on the inner bottom surface 5 and the inner peripheral surface 6 of the recess 4 of the Si base material 1, and each electrode pattern 12 a and 12 b passes from the inner bottom surface 5 through the inner peripheral surface 6. It extends to the first side surface 2 and leads to scraping surfaces 13 a and 13 b that sandwich the first side surface 2.

  Furthermore, electrode patterns 12 a and 12 b are also formed on the inner surface of the through-hole 9, and the electrode patterns 12 a and 12 b on the first side surface 2 pass through the through-hole 9 and the second side surface on which the other opening of the through-hole 9 is provided. 14, leading to scraping surfaces 13 c and 13 d that are connected to the electrode patterns 12 a and 12 b formed on the second side surface 14 and sandwich the second side surface 14.

  Electrodes are three-dimensionally formed on the electrode patterns of the scraped surfaces 13a to 13d, and are connected to an external circuit to form external circuit bonding electrodes 15a to 15d for introducing electric power. Accordingly, the pair of electrode patterns 12a, 12b formed on the inner bottom surface 5 and the inner peripheral surface 6 of the recess 4 are external circuit bonding electrodes 15a provided on the scraping surfaces 13a, 13c and 13b, 13c of the Si base 1, respectively. , 15c and 15b, 15c are electrically connected.

  The LED chip 16 is placed on one electrode pattern 12a of the electrode turns 12a and 12b formed on the inner bottom surface 5 of the recess 4, and the lower electrode of the LED chip 16 and the electrode pattern 12a are connected by eutectic bonding. The external circuit junction electrodes 15a and 15c are electrically connected. On the other hand, the upper electrode of the LED chip 16 is connected to the other electrode pattern 12b of the inner bottom surface 5 of the recess 4 through the bonding wire 17, and is electrically connected to the external circuit bonding electrodes 15b and 15d. The LED chip has a nitride semiconductor active layer that emits light having a peak wavelength of 480 nm or less on a translucent SiC substrate, and has an AuSn or Sn eutectic electrode as a lower electrode.

  Furthermore, the recess 4 is filled with a light-transmitting sealing resin 18 to seal the LED chip 16 and the bonding wire 17 with resin. As the sealing resin, silicone resin, epoxy resin, polyolefin resin, silicone-epoxy resin, PVA resin, fluorine resin, or the like is used.

  The surface mount type semiconductor light emitting device represented by the perspective view shown from the front side of FIG. 4 and the perspective view shown from the back side of FIG. 5 is connected to the external circuit in the first embodiment shown in FIGS. Instead of the through-holes (through holes) provided to connect the electrodes 15a and 15c, 15b and 15d, the sides 15a and 15c and 13b are formed in a shape with the sides greatly cut away. And 13d are connected to each other, and the external circuit bonding electrodes 15a and 15c and 15b and 15d formed on each scraping surface are integrated. Other configurations are the same as those of the first embodiment shown in FIGS.

  FIG. 6 is a cross-sectional view showing a second embodiment relating to the surface-mounted semiconductor light-emitting device of the present invention. In the present embodiment, recesses 4a and 4b having openings are provided on the first side surface 2 side and the second side surface 14 side, respectively, and a pair of electrode patterns 12a separated on the inner bottom surface and inner peripheral surface of each recess 4a and 4b. , 12 and 12c, 12d are formed, and the electrode patterns 12a, 12b, 12c, 12d are connected to the positions corresponding to the independent scraping surfaces 13a, 13b, 13d, 13c shown in FIG. External circuit bonding electrodes 15a, 15b, 15d, and 15c formed in a three-dimensional manner are provided on the cutting surfaces 13a, 13b, 13d, and 13c.

  The LED chip 16 is placed on one electrode pattern 12a, 12c of the electrode turns 12a, 12b, 12c, 12d formed on the inner bottom surface of each recess 4a, 4b, and the lower electrode and electrode of each LED chip 16 are placed. The patterns 12a and 12c are connected by eutectic bonding and are electrically connected to electrodes corresponding to the external circuit bonding electrodes 15a and 15d shown in FIG. On the other hand, the upper electrode of each LED chip 16 is connected to the other electrode patterns 12b and 12d of the inner bottom surface 5 of the recess 4 through bonding wires 17, and corresponds to the external circuit bonding electrodes 15b and 15c shown in FIG. Electrically conducting.

  Further, each of the recesses 4a and 4b is filled with a translucent sealing resin 18 to seal the LED chip 16 and the bonding wire 17 with resin. As the sealing resin, silicone resin, epoxy resin, polyolefin resin, silicone-epoxy resin, PVA resin, fluorine resin, or the like is used.

  The surface-mount type semiconductor light-emitting device of this example is a double-sided light emitting type that emits light emitted from the LED chip in the opposite direction from opposite surfaces.

  7 and 8 show the state when the first embodiment is mounted on a mother board, and FIG. 9 shows the state when the second embodiment is mounted on a mother board. Example 1 is a top-view type mounting method in which the light emission direction of the semiconductor light-emitting device is substantially perpendicular to the mounting surface of the motherboard as shown in FIG. 7, and the light of the semiconductor light-emitting device as shown in FIG. Both the mounting method and the side view type mounting method in which the discharge direction is mounted so as to be substantially parallel to the mounting surface of the motherboard can be used.

  In any mounting method, the semiconductor light-emitting device is solder-bonded to the motherboard with a surface parallel to and perpendicular to the mother board of the external circuit bonding electrode formed on the semiconductor light-emitting device. The type semiconductor light emitting device is firmly mounted, and a highly reliable mounting can be ensured.

Next, a manufacturing process related to the surface mount semiconductor light emitting device of the present invention will be described with reference to FIGS. FIG. 10 shows a process for producing a multi-chamfered Si base material from an Si wafer, and FIG. 11 shows a process for forming an electrode pattern on the multi-chamfer Si base material. First, referring to FIG. 10, a Si wafer is prepared in the step (a). In the step (b), a thermal oxide film is formed on the (100) surface of the Si wafer. In the step (c), a resist is spin-coated on the oxide film and prebaked. In step (d), the resist is exposed to a mask and developed to remove the resist in the etched portion of the Si wafer and leave the resist in other portions. In the step (e), after post-prebaking, the oxide film is selectively etched with buffered hydrofluoric acid (BFH) in which hydrofluoric acid (HF) and ammonium fluoride (NH ₄ F) are mixed using the resist as a mask. In the step (f), after removing the resist, RCA1 (1pNH ₃ (25%) + 5pH ₂ O + 1pH ₂ O ₂ ) cleaning and RCA2 (1pHCl + 6pH ₂ O + 1PH ₂ O ₂ ) cleaning are performed and then immersed in HF. In the step (g), the remaining oxide film is used as a mask to etch the Si wafer by KOH-based alkaline wet etching to form a recess having the (111) plane as an etching slope. In the step (h), the oxide film is removed to complete a multi-cavity Si substrate.

In the step (g) of etching the Si wafer, TMAH (tetramethylammonium hydroxide), EDP (ethylenediamine pyrocatechol), and N ₂ H ₄ + H ₂ O can be used in addition to KOH. Further, etching by a dry process such as XeF ₂ or SF ₆ + C ₄ H ₈ Bosch process, formation of a recess by a dicing process using a blade having a concave slope, and formation of a recess by blasting are also possible. Further, depending on the etching method, the slope angle can be controlled by changing the surface orientation of etching.

  Thereafter, the process proceeds to the electrode pattern forming step shown in FIG. From FIG. 11, a multi-chamfer Si substrate is prepared in the step (a). In the step (b), a thermal oxide film is formed on the multi-chamfered Si substrate. In the step (c), a resist is applied on the oxide film and prebaked. In step (d), the resist is mask-exposed and developed to remove the resist where the electrode pattern is to be formed, and leave the resist in the other portions. In the step (e), Ti / Ni / AgBiNd to be an electrode pattern is formed by vapor deposition or sputtering. In step (f), when the resist is removed by removing the resist with a stripping solution, an electrode pattern is formed on the multi-faced Si substrate.

  In the step of forming the electrode pattern of (e) above, in addition to Ti / Ni / AgBiNd film formation, Ti / Ni / Au, Cr / Ni / Au, TiW / Au, Ti / NiV / Au, Cr / NiV / Au, Ti / Ni / AgNdCu, Cr / Ni / AgNdCu, TiW / AgNdCu, Ti / Ni / AgBi, Cr / Ni / AgBi, TiW / AgBi, Cr / Ni / AgBiNd, TiW / AgBiNd, Cr / NiV / AgBiNd , Ti / Ni / AgBiAu, Cr / Ni / AgBiAu, TiW / AgBiAu, Cr / NiV / AgBiAu, etc. The final surface has a surface roughness (Ra) of 0.1 μm or more and is not sulfided or oxidized by light such as Ag. It is also possible to form a film with such a material.

  Alternatively, as another electrode forming method, a Cu thin film is formed by electroless plating, and then a Cu thick film is formed by electroforming. The resist is left in the portion where the electrode pattern is to be formed, and the other portions of the resist are removed. Then, a desired electrode pattern can be obtained by etching the Cu thick film exposed with ferric chloride. Furthermore, Au, AgBi, Pd, AgPd, Ag / Re, Ag / Rh, and the like can be formed on the Cu electrode pattern by electrolytic plating to form an electrode pattern capable of eutectic bonding.

  Etching solution for Cu thick film includes cupric chloride, ammonium persulfide as the main component, ammonium persulfide as ammonia complex, sulfuric acid / hydrogen peroxide as main component, sulfuric acid / peroxide Those obtained by complexing hydrogen with ammonia or those mainly composed of chlorate can be used.

Furthermore, a method of providing an external circuit bonding electrode on the electrode pattern is formed by injecting a quantitative amount of AuSn paste on the electrode pattern with a dispenser and reacting at the eutectic temperature. Further, by depositing Au on the surface of AuSn by means of barrel plating or performing solder plating, it is possible to improve the solder wettability at the time of solder joining with the external electrode terminal.
In addition to AuSn, a paste such as AuSi or AuGe may be used. Depending on the film formation on the surface, a paste of Au and Ag may be used.

  Up to this point, the process of processing a Si wafer into a desired shape and producing a multi-faced Si substrate on which necessary electrode patterns and external circuit bonding electrodes are formed has been described. LED chips are placed in a plurality of recesses provided on the Si base, bonding wires are aerially wired, sealing resin is filled in the recesses, heat-cured, and finally a multi-faced Si substrate at predetermined intervals Each surface-mount type semiconductor light-emitting device is completed by cutting and separating.

  As a light source of the surface-mount type semiconductor light emitting device of the present invention, an LED chip that emits light in a wavelength (frequency) region from ultraviolet to visible to infrared can be used. Although all LED chips that emit light in the above-mentioned wavelength range are targeted as light emission sources of monochromatic light emitting semiconductor light emitting devices, as described in “Background Art”, a part of the light emitted from the LED chips is fluorescent. A semiconductor light emitting device that excites a substance, converts the wavelength, and emits light having a color tone different from the light emitted from the LED chip is possible. As the light source in that case, for example, as an LED chip that emits blue light, the nitride-based semiconductor that emits light having a peak wavelength of 480 nm or less on the translucent SiC substrate mentioned in the above embodiment In addition to the LED chip having the active layer, there are materials such as TiON, and the LED chips that emit ultraviolet light include InGaN, AlGaN, ZnS, ZnO, and TiO materials.

  As a fluorescent substance that receives light emitted from an LED chip made of these materials, converts the wavelength and emits light of a different wavelength, for example, by mixing a silicate fluorescent substance into a sealing resin, for example, The color tone of the light emitted by converting the blue light having the peak wavelength of 463 nm into the green light having the peak wavelength of 563 nm also changes.

In general, as a fluorescent substance that receives light in a shorter wavelength region than yellow light emitted from an LED chip and brings yellow light to wavelength conversion and color tone change, a general formula of R ₃ M ₅ O ₁₂ : Ce, Pr Wherein R is at least one element of yttrium (Y) and gadolinium (Gd), and M is at least one element of aluminum (Al) and gallium (Ga). Or a fluorescent substance based on oxynitride glass, or thiogallate CaGa ₂ S ₄ : Eu.

Further, a fluorescent substance that receives light in a shorter wavelength region than the green light emitted from the LED chip and brings the wavelength conversion and color tone change into the green light is represented by the general formula of Y ₃ M ₅ O ₁₂ : Ce. Among the fluorescent substances, a fluorescent substance in which M is at least one element of aluminum (Al) and gallium (Ga), thiogallate SrGa ₂ S ₄ : Eu, silicate fluorescent substance Ca ₃ Sr (SiO ₄ ) ₃ : Ce, oxide fluorescent substance CaSr ₂ O ₄ : Ce, oxynitride fluorescent substance SrSi ₂ O ₂ N ₂ : Eu, and the like can be given.

In addition, as a fluorescent material that receives light in a shorter wavelength region than red light emitted from the LED chip and causes wavelength conversion and color tone change to red light, it is represented by a general formula of sulfide-based fluorescent material M ₅ S: Eu. Among the fluorescent materials to be used, M includes nitride-based fluorescent materials CaSiN ₂ : Eu, CaAlSiN ₂ : Eu, and the like.

Also, when obtaining white light by ultraviolet light emitted from the LED chip,
Aluminate phosphor BaM ₂ Al ₁₆ O ₂₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, halophosphate phosphor (Sr, Ca, Ba) ₅ (PO ₄ ) ₃ Cl: Eu, wavelength-converted into blue light
Aluminate fluorescent material BaMg ₂ Al ₁₆ O ₂₇ : Eu, Mn, halosilicate fluorescent material Ca ₈ Mg (SiO ₄ ) ₄ Cl: Eu, Mn, silicate fluorescent material ((Ba, Sr) , Ca, Mg) _1-X Eu _X ) ₂ SiO ₄ , Zn ₂ GeO ₄ : Mn,
Oxysulfide fluorescent substance Y ₂ O ₂ S: Eu, Y ₂ O ₃ : Eu, Bi, thiogallate (Sr, Ca, Ba) (Al, Ga) ₂ S ₄ : Eu, wavelength-converted into red light
In this case, a fluorescent material that is appropriately selected and mixed from fluorescent materials that convert the wavelength of blue light, green light, and red light can be used.

Furthermore, the other as a fluorescent substance that converts the wavelength to red _light, A in _{(Eu 1-x-y M} x Sm y) (W 1-z Mo z) 2 O 8 ( where the equation, A is Li, Na , K, Rb, and Cs, and M is B, Al, Sc, Ga, In, Tl, Sb, Bi, Y, La, Gd, Lu, Nb, Ta, Hf And at least one selected from the group consisting of the elements P and x, 0 ≦ x ≦ 0.3, y is 0 <y ≦ 0.1, and z is 0 ≦ z ≦ 1.

Similarly, as a fluorescent substance that converts the wavelength of red light into LED light in the blue wavelength region from the long ultraviolet wavelength region, Eu ³⁺ ions arranged in two dimensions or one dimension in AEuXLn _1-x M ₂ O ₈ (however, 0 <x ≦ 1, A in the composition is at least one of the group consisting of elements of Li, Na, K, Rb and Cs, and Ln is in the group consisting of elements of Y, La, Gd and Lu. And M is one of W and Mo.).

In addition, when white is obtained by additive color mixing of light of R (red), G (green), and B (blue), (2-xy) as a fluorescent substance that compensates for the lack of yellow light in the white spectral characteristics. _{SrO · x (Ba, Ca)} O · (1-a-b-c-d) SiO 2 · aP 2 O 5 bAl 2 O 3 cB 2 O 3 dGeO 2: y Eu 2+ ( where, 0 <x <1 .6, 0.005 <y <0.5, 0 <a, b, c, d <0.5.) Alkaline earth metal orthosilicate activated with divalent europium (2-x-y) BaO · x (Sr, Ca) O · (1-a-b-c-d) SiO 2 · aP 2 O 5 bAl 2 O 3 cB 2 O 3 dGeO 2: y Eu 2+ ( 0.01 <x <1.6, 0.005 <y <0.5, 0 <a, b, c, d <0.5.) Potassium earth metal orthosilicate, structurally stable oxynitride glass such as oxynitride glass, β-sialon, α-sialon as materials that can shift excitation light and light emission to the longer wavelength side, and oxynitride fluorescence containing nitrogen in the structure Substances can be mentioned.

  As described above, in the surface mount semiconductor light emitting device of the present invention, a semiconductor light emitting element (LED chip) is placed on a Si base material obtained by processing a Si wafer by eutectic bonding. . Therefore, even under the high temperature environment during eutectic bonding of semiconductor light emitting devices, the Si substrate is not affected by high heat, and at the same time, the Si substrate is directly mounted on the motherboard, so the heat dissipation effect is also good. It is. Further, even when the Si substrate is exposed to a high temperature and high humidity environment and a light environment in a short wavelength region, there is almost no deterioration in characteristics.

  Therefore, it is possible to realize a surface mount semiconductor light emitting device capable of maintaining high light emission efficiency and high light extraction efficiency over a long period of use from the manufacturing process. In addition, the external circuit connection electrode for introducing power by connecting to the external electrode is directly provided on the Si base material in three dimensions, and the device is devised to provide the external circuit connection electrode.

As a result, reliable mounting on the motherboard is ensured, top-view type mounting and side-view type mounting can be combined, the mounting flexibility is improved, and the cost can be reduced by sharing parts. it can. In addition, since a large number of semiconductor light emitting devices can be formed on the multi-chamfered Si substrate, cost reduction can be realized also in this respect. Furthermore, since a double-sided light emitting type surface mount semiconductor light emitting device can be realized, the degree of freedom in design can be increased.

It is the perspective view which showed Example 1 of the surface mounted semiconductor light-emitting device of this invention from the surface side. Similarly, it is the perspective view which showed Example 1 of the surface mounted semiconductor light-emitting device of this invention from the back surface side. It is AA sectional drawing of FIG. It is the perspective view which showed other forms of Example 1 of the surface mounted semiconductor light-emitting device of this invention from the surface side. Similarly, it is the perspective view which showed the other form of Example 1 of the surface mounted semiconductor light-emitting device of this invention from the back surface side. It is sectional drawing of Example 2 of the surface mount-type semiconductor light-emitting device of this invention. It is a front view which shows the mounting state of Example 1 of the surface mounted semiconductor light-emitting device of this invention. Similarly, it is a front view which shows the mounting state of Example 1 of the surface mounted semiconductor light-emitting device of this invention. It is a front view which shows the mounting state of Example 2 of the surface mounted semiconductor light-emitting device of this invention. It is process drawing which shows a part of manufacturing process of the surface mount-type semiconductor light-emitting device of this invention. Similarly, it is process drawing which shows a part of manufacturing process of the surface mounted semiconductor light-emitting device of this invention. It is a top view which shows the conventional surface mount type semiconductor light-emitting device. It is AA sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Si base material 2 1st side surface 3 Opening 4, 4a, 4b Recessed part 5 Inner bottom face 6 Inner peripheral surface 7 Opening edge part 8 End surface edge part 9 Through-hole 10 Side edge (ridge)
11 End face 12a, 12b Electrode pattern
13a, 13b, 13c, 13d Cutting surface 14 Second side
15a, 15b, 15c, 15d External circuit bonding electrode 16 LED chip 17 Bonding wire 18 Sealing resin 20 Oxide film

Claims (8)

  A plurality of electrode patterns separated by an insulating layer are formed on the surface of the Si substrate on which the recesses having openings are formed, and at least two of the electrode patterns have external circuit connection electrodes on at least one place. A semiconductor light emitting element is mounted on the electrode pattern disposed on the bottom surface of the recess by eutectic bonding, and is wired overhead via a bonding wire, and the recess is filled with a sealing resin to emit the semiconductor light. A surface-mount type semiconductor light-emitting device in which an element and the bonding wire are sealed with resin.   The external circuit connection electrodes are three-dimensionally formed and have a surface that is substantially parallel to the surface of the surface-mount semiconductor light-emitting device that faces the motherboard when the surface-mount semiconductor light-emitting device is mounted on the mother board. The surface-mount type semiconductor light-emitting device according to claim 1, comprising:   The surface-mounting semiconductor light-emitting device according to claim 1, wherein the sealing resin contains one or more fluorescent substances mixed in a translucent resin.   A mounting method in which an optical axis is oriented in a direction substantially perpendicular to the motherboard, and a mounting method in which an optical axis is oriented in a direction substantially parallel to the motherboard with respect to the motherboard on which the surface-mounted semiconductor light emitting device is mounted. The surface-mounting type semiconductor light-emitting device according to claim 1, wherein both mounting methods are possible.   A plurality of electrode patterns separated by an insulating layer are formed on the surface of the Si base formed on the opposite side of the two concave portions having openings, and at least four of the electrode patterns have at least one place above External circuit connection electrodes are provided, semiconductor light-emitting elements are mounted by eutectic bonding on the electrode patterns disposed on the bottom surfaces of the respective recesses, and aerial wiring is performed via bonding wires, and the respective recesses are disposed in the recesses. A surface-mount type semiconductor light-emitting device, wherein the semiconductor light-emitting element and the bonding wire are filled with a sealing resin and sealed with resin.   The external circuit connection electrodes are three-dimensionally formed and have a surface that is substantially parallel to the surface of the surface-mount semiconductor light-emitting device that faces the motherboard when the surface-mount semiconductor light-emitting device is mounted on the mother board. The surface-mount type semiconductor light-emitting device according to claim 5, comprising:   The surface-mounting semiconductor light-emitting device according to claim 5, wherein the sealing resin contains one or more fluorescent substances mixed in a translucent resin.   With respect to the mother board on which the surface-mount type semiconductor light emitting device is mounted, the optical axis is in a direction substantially parallel to the mother board, and the light emitting directions of the semiconductor light emitting elements mounted on the two recesses are opposite to each other. The surface-mounting type semiconductor light-emitting device according to claim 5, wherein a simple mounting method is possible.

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