JP2012044048A - Method for manufacturing light emitting element package and light emitting element package - Google Patents

Abstract

The object of the present invention is to avoid a decrease in light extraction efficiency due to a wall of a light emitting element package, and to make a wavelength conversion material kneaded in a sealing resin into a layer that is uniformly distributed on or around the light emitting element. A manufacturing method of a light emitting device package and a light emitting device package are provided.
A manufacturing method of an LED package comprising a substrate, an LED chip mounted on the substrate, and a sealing resin kneaded with a phosphor for sealing the LED chip. A liquid repellent pattern forming step for forming the liquid repellent pattern 5 on the substrate 1, a mounting step for mounting the LED chip 3 on the inside of the liquid repellent pattern 5 on the substrate 1, and a phosphor 8 is kneaded inside the liquid repellent pattern 5. An application process for applying the sealing resin 4 and a sedimentation process for precipitating the phosphor 8 in the sealing resin 4 in a windless state are included.
[Selection] Figure 1

Description

  The present invention relates to a method of manufacturing a light emitting device package in which the light emitting device is sealed with a resin layer and the light emitting device package, and in particular, a resin layer in a phosphor when a monochromatic LED chip and a phosphor are used. The present invention relates to prevention of unevenness such as chromaticity in the sedimentation process.

  Light emitting elements such as light emitting diodes (LEDs) have features such as low power consumption, small size, and light weight. For this reason, it is applied to various fields as a light source of various illumination devices such as a backlight for a liquid crystal display panel, a signal lamp, and an indicator lamp. When the LED is applied as a light source, an LED package in which the LED is sealed is used. The LED package has a structure in which LED chips electrically and mechanically connected to a substrate such as a flat interposer substrate are sealed with a sealing resin.

  By the way, many of the LEDs used for the backlight for the liquid crystal display panel are white LEDs that emit white light. There are mainly two types of methods for realizing this white LED. One is a method using a monochromatic LED chip and a phosphor, and the other is a method using a combination of red, green and blue LED chips. At present, the former method is mainly used because the cost of the latter LED chip is high.

  Examples of the method of using the LED chip and the phosphor described above include a method of combining a blue LED chip and a yellow phosphor, and a combination of a blue LED chip, a red phosphor and a green phosphor in order to improve color rendering. There are methods. According to these methods, since the phosphor converts blue light into yellow light, part of the blue light emitted from the blue LED transmits the phosphor layer and emits blue light, while the remaining blue light is emitted. Hits the phosphor and becomes yellow light. Therefore, the concrete mechanism is that these two colors are mixed and appear white.

  Here, as a light emitting device using an LED chip and a phosphor, for example, there is one disclosed in Patent Document 1.

  As shown in FIG. 8, the light emitting device 100 includes a light emitting element 102 mounted on the terminal plates 101a, 101b, and 101c of the lead frame 101, a package 110 in which the light emitting element 102 is mounted on the bottom surface 111a of the recess 111, The recess 111 is provided with a resin sealing portion 113 formed by filling and curing a translucent resin containing the phosphor 112.

  In the light emitting device 100 using the phosphor 112, it is important to dispose the phosphor 112 in a layer shape having a substantially uniform thickness near the bottom surface of the translucent resin in order to suppress variations in chromaticity.

  In order to solve this problem, in the light emitting device 100 disclosed in Patent Document 1, the inner peripheral wall surface 111b of the recess 111 is formed to be an inclined surface in which the angle formed by the entire wall surface and the bottom surface 111a is an acute angle. ing. As a result, the phosphor 112 positioned in the vicinity of the inner peripheral wall surface 111b settles as it is without being fixed to the inner peripheral wall surface 111b, and settles on the bottom surface 111a.

  As a result, the phosphor 112 can be formed as an average layer distributed on the bottom surface 111a and the light emitting element 102 without applying vibration to the base filled with the translucent resin containing the phosphor 112. It is possible to suppress a decrease in reliability while suppressing variation in degree.

  Further, for example, in the light emitting diode 200 disclosed in Patent Document 2, as shown in FIG. 9, the LED chip 202 disposed on the support 201 and at least a part of the light emitted from the LED chip 202 are absorbed. A resin 204 containing a particulate fluorescent material 203 that emits light after wavelength conversion is included. Also in the light emitting diode 200, the resin 204 containing the particulate fluorescent material 203 is applied to the concave portion 205 a of the package 205, is allowed to settle in the resin 204 of the particulate fluorescent material 203, and is disposed on the LED chip 202. The thickness of the particulate fluorescent material 203 is made substantially equal to the thickness of the particulate fluorescent material 203 disposed on the support 201 other than the LED chip 202.

  As described above, in the LED package manufacturing method disclosed in Patent Document 1, Patent Document 2, and the like, a phosphor-containing resin is applied to a substrate having a recess to precipitate the phosphor. As a result, there is a wall around the phosphor-containing resin, and the applied phosphor-containing resin has a uniform depth, so that sedimentation can be performed uniformly, and variations in chromaticity during mass production can be reduced. There is.

  Here, the reason for precipitating the phosphor is as follows. In other words, it is possible to cure the resin without precipitating the phosphor, but even when using a resin with high viscosity, the resin viscosity decreases and the microprecipitation occurs in the process of increasing the temperature to the thermosetting temperature. There is. In this case, the chromaticity is likely to vary depending on the progress of sedimentation. For this reason, it is advantageous to suppress the dispersion when the resin is completely settled out of the kneaded resin. There is also an advantage that the color conversion efficiency is good.

JP 2010-27756 A (published February 4, 2010) Japanese Patent Laid-Open No. 11-40858 (published on February 12, 1999)

  However, in the manufacturing method of the light emitting element package manufacturing method disclosed in the above-described conventional Patent Document 1 and Patent Document 2, the package has a recess. However, the manufacturing of the package in which the recess is processed is costly. In addition, the light extraction efficiency is poor due to the package wall having the recesses.

  Therefore, in order to solve these problems, it is conceivable to form a phosphor layer on the LED chip by forming a liquid repellent pattern on a flat substrate and applying a phosphor kneaded resin inside the liquid repellent pattern. . Thereby, it is possible to improve the light extraction efficiency while solving the problem of cost for processing the concave portion of the substrate.

  However, when the liquid repellent pattern is used, there is a new problem that uniform sedimentation is difficult when the phosphor is sedimented.

  This is because, in order to lower the viscosity of the resin, the phosphor is precipitated under a temperature condition higher than normal temperature, but in that case, when using an oven generally used for heating, around the resin This is because there is no wall, so it is easily affected by the wind in the oven.

  The present invention has been made in view of the above-described conventional problems, and the object thereof is to avoid a decrease in light extraction efficiency due to the wall of the light emitting device package and to be kneaded with a sealing resin. An object of the present invention is to provide a low-cost method for manufacturing a light-emitting element package and a light-emitting element package in which the wavelength conversion material can be a layer uniformly distributed on or around the light-emitting element.

  In order to solve the above problems, a method for producing a light emitting device package of the present invention includes a substrate, a light emitting device mounted on the substrate, and a sealing resin kneaded with a wavelength conversion material for sealing the light emitting device. A liquid repellent pattern forming step for forming a liquid repellent pattern on the substrate, a mounting step for mounting the light emitting element inside the liquid repellent pattern on the substrate, and the liquid repellent pattern It includes an application step of applying a sealing resin kneaded with the wavelength conversion material inside, and a sedimentation step of precipitating the wavelength conversion material in the sealing resin in a windless state.

  According to the invention, the liquid repellent pattern forming step for forming the liquid repellent pattern on the substrate, the mounting step for mounting the light emitting element inside the liquid repellent pattern on the substrate, and the wavelength conversion inside the liquid repellent pattern. An application step of applying a sealing resin kneaded with the material.

  That is, in the present invention, since the sealing resin is molded by the liquid repellent pattern, there is no wall in the light emitting element package. For this reason, it can avoid that the light extraction efficiency falls because of the wall of the light emitting device package.

  Further, since the light emitting element package does not have the recess for the sealing resin, the cost for forming the recess for the sealing resin in the light emitting element package is unnecessary. Therefore, it is possible to provide a low-cost method for manufacturing a light emitting device package.

  Here, when the sealing resin is molded with a liquid repellent pattern using a flat substrate, and the wavelength conversion material in the sealing resin is deposited on the top surface of the light emitting element in the sedimentation step, the viscosity of the sealing resin is set. When using a commonly used oven for heating to raise, there is no wall around the sealing resin, so it is difficult to form a uniform deposited layer of wavelength conversion material under the influence of wind in the oven It becomes.

  Therefore, in the present invention, in the sedimentation step, the wavelength conversion material in the sealing resin is sedimented in a windless state. As a result, the wavelength conversion material can be allowed to settle without being affected by wind, so that a deposited layer of the wavelength conversion material having a constant film thickness can be formed on the upper surface of the light emitting element and its periphery.

  Therefore, it is possible to avoid a decrease in light extraction efficiency due to the wall of the light emitting device package, and to reduce the cost by which the wavelength conversion material kneaded in the sealing resin can be uniformly distributed on or around the light emitting device. A method for manufacturing the light emitting device package can be provided.

  In the method for manufacturing a light emitting device package of the present invention, the viscosity η of the sealing resin is

However, it is preferable that h: height of the sealing resin, ρ: specific gravity of the wavelength conversion material, ρ _w : specific gravity of the sealing resin, g: gravitational acceleration, r: particle radius of the wavelength conversion material.

Accordingly, the wavelength kneaded in the sealing resin according to the height h of the sealing resin, the specific gravity ρ of the wavelength conversion material, the specific gravity ρ _{w of the} sealing resin, the gravitational acceleration g, and the particle radius r of the wavelength conversion material. An appropriate condition for the viscosity η of the sealing resin can be set for allowing the conversion material to settle and forming the layer uniformly distributed on or around the light emitting element.

  In the method for manufacturing a light emitting element package according to the present invention, the light emitting element package includes at least one pair of electrodes, one or more light emitting elements, an element bonding resin for bonding the substrate and the light emitting elements, and a hemispherical surface. It is possible to have a sealing resin.

  Thereby, for example, a method for manufacturing a light emitting device package including a plurality of light emitting devices can be provided. Further, by making the surface shape of the sealing resin hemispherical, the amount of the sealing resin used can be minimized and the cost can be reduced. Furthermore, the amount of wavelength conversion material deposited on the side wall of the light emitting element is adjusted by bonding the substrate and the light emitting element using the element bonding resin, for example, by filling the element bonding resin to the side surface of the light emitting element. can do. Thereby, on the side surface of the light emitting element, it is possible to prevent a chromaticity variation from occurring due to a step formed in the deposition layer of the wavelength conversion material and the light emitting element being exposed.

  In the method for manufacturing a light emitting element package according to the present invention, it is preferable that the element bonding resin is provided so as to be inclined so that a fillet portion on the outer periphery of the light emitting element reaches the upper surface of the light emitting element.

  Thereby, the wavelength conversion material is also deposited on the upper surface of the outer peripheral fillet portion of the light emitting element. Therefore, on the side surface of the light emitting element, it is possible to prevent a variation in chromaticity from occurring due to a step formed in the deposition layer of the wavelength conversion material and exposing the light emitting element.

  In the light emitting device package manufacturing method of the present invention, it is preferable that the wavelength conversion material has a higher specific gravity than the sealing resin, and in the sedimentation step, the wavelength conversion material settles in the sealing resin by gravity.

  For example, as a method for depositing the wavelength conversion material, sedimentation by weight, centrifugation, adsorption by electromagnetic force, and the like can be considered. However, the method of allowing the inside of the sealing resin to settle by gravity is the simplest and leads to low cost.

  In the method for manufacturing a light emitting device package of the present invention, it is preferable that the sedimentation step is performed in a temperature range from 0 ° C. to less than the thermosetting temperature of the sealing resin.

  Thereby, it becomes possible to adjust the viscosity of sealing resin in the temperature range from 0 degreeC to less than the thermosetting temperature of sealing resin, and it becomes possible to control the sedimentation rate of wavelength conversion material appropriately.

  In the method for manufacturing a light emitting device package of the present invention, in the sedimentation step, the temperature of the sealing resin can be adjusted by a lamp or a hot plate. For example, a halogen lamp or an infrared lamp can be used as the lamp. In addition to a general hot plate, a stacked hot plate or a belt conveyor type hot plate can be used as the hot plate.

  Thereby, since an oven is not used, the wind accompanying the use of the oven can be prevented, and the loss of uniformity in the deposited layer of the wavelength conversion material can be prevented.

  In the method for manufacturing a light emitting device package of the present invention, in the sedimentation step, the entire package of the light emitting device can be sealed with a sealed container.

  Thus, the effect of wind can be avoided because the entire package of the light-emitting element is sealed in a sealed container, whether it is settling at room temperature or settling using an oven.

  In order to solve the above problems, a light emitting device package of the present invention is manufactured using the above-described method for manufacturing a light emitting device package.

  According to the above invention, the light conversion efficiency is prevented from decreasing due to the wall of the light emitting device package, and the wavelength conversion material kneaded in the sealing resin is uniformly distributed on and around the light emitting device. A low-cost light-emitting element package that can be used as a layer can be provided.

  As described above, the method for manufacturing a light emitting device package according to the present invention includes a liquid repellent pattern forming step for forming a liquid repellent pattern on a substrate, a mounting step for mounting a light emitting device on the inside of the liquid repellent pattern on the substrate, An application step of applying a sealing resin kneaded with the wavelength conversion material inside the liquid repellent pattern; and a sedimentation step of precipitating the wavelength conversion material in the sealing resin in a windless state.

  As described above, the light emitting device package of the present invention is manufactured using the method for manufacturing a light emitting device package described above.

  Therefore, it is possible to prevent the light extraction efficiency from being lowered due to the wall of the light emitting device package, and to make the wavelength conversion material kneaded in the sealing resin into a layer uniformly distributed on or around the light emitting device. There is an effect of providing a cost-effective method for manufacturing a light emitting device package and a light emitting device package.

1 shows an embodiment of an LED package according to the present invention, and is a cross-sectional view showing a configuration of the LED package. (A) (b) (c) is a top view which shows the manufacturing method of the said LED package. (A)-(c) is sectional drawing which shows the deposition condition of a fluorescent substance when there exists a wind etc. in the sedimentation process in the sealing resin of the fluorescent substance in an LED package. It is a schematic diagram which shows the LED package used when examining the uniformity of the thickness of a fluorescent substance layer from the comparison of the height of the fluorescent substance layer of center part A and the peripheral part B. FIG. It is a graph which shows the relationship between center part A / peripheral part B and the viscosity of sealing resin in the schematic diagram of FIG. It is sectional drawing which shows the irradiation light from the LED chip of the said LED package. FIG. 5 is a cross-sectional view showing still another embodiment of the LED package according to the present invention and showing the configuration of the LED package. It is sectional drawing which shows the structure of the conventional LED package. It is sectional drawing which shows the structure of the other conventional LED package.

[Embodiment 1]
One embodiment of the present invention will be described below with reference to FIGS.

(Configuration of LED package)
First, a configuration of an LED (Light Emitting Diode) package as a light emitting element package according to the present embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view showing a configuration of an LED (Light Emitting Diode) package 10 as a light emitting element package according to the present embodiment.

  As shown in FIG. 1, an LED package 10 according to the present embodiment includes a pair of electrodes 2 and 2, an LED chip 3 as two light emitting elements, and an LED chip 3 sealed on a substrate 1. And a liquid repellent pattern 5 provided on the outer edge of the sealing resin 4.

  The substrate 1 is an interposer wiring substrate on which the LED chip 3 is mounted. As the substrate 1, a glass substrate, a ceramic substrate, a printed substrate or the like can be used, but is not particularly limited.

  One of the electrodes 2 and 2 is an anode electrode, and the other is a cathode electrode. The electrodes 2 and 2 are wiring patterns for the LED chip 3 formed on the substrate 1. Although not shown, a part of the electrodes 2 and 2 is insulated from others by an insulating member such as glass.

  The LED chip 3 is disposed between the electrodes 2 and 2 and is fixed to the substrate 1 with a die bond bonding agent 6 as an element bonding resin. The LED chip 3 is connected to the electrodes 2 and 2 by wires 7 and 7. Thereby, the board | substrate 1 and LED chip 3 are connected electrically and mechanically.

  In FIG. 1, two LED chips 3 are installed at the center of the substrate 1. The number of LED chips 3 to be installed is not particularly limited and may be one or more. Further, the emission color of the LED chip 3 is not particularly limited. In the present embodiment, the LED chip 3 is a light emitting element, but other light emitting elements such as a semiconductor laser and an organic EL element can also be used.

  The sealing resin 4 seals the LED chip 3 and the wires 7 and 7. Examples of the sealing resin 4 include silicone resins, epoxy-modified silicone resins, alkyd-modified silicone resins, acrylic-modified silicone resins, polyester-modified silicone resins, and phenyl silicone resins, epoxy resins, acrylic resins, methacrylic resins, and urethane resins. It is formed from transparent resin.

  The sealing resin 4 is preferably transparent, but is not necessarily transparent if it can transmit most of the light emission of the LED chip 3 and the light emission of the phosphor 8 described later in the sealing resin 4. There is no need. Further, the transparent resin constituting the sealing resin 4 is preferably as high as possible, and it is desirable that the refractive index has a small difference in refractive index from the outside (air). Moreover, if the surface of the sealing resin 4 is a spherical shape such as a dome shape as in the present embodiment, reflection at the interface between the sealing resin 4 and the outside can be reduced. Therefore, the light extraction efficiency of the LED package 10 can be increased.

  In the sealing resin 4, a phosphor 8 is mixed as a wavelength conversion material that emits light when excited by the emitted light of the LED chip 3. Examples of the phosphor 8 include a yellow phosphor, a red phosphor, and a green phosphor.

  In the present embodiment, in the manufacturing process, the phosphor 8 is kneaded into the flexible sealing resin 4 and settled for a certain time, so that the phosphor 8 has a uniform thickness on the upper surface of the LED chip 3 and the upper surface of the substrate 1. It has a distributed layer.

  Due to the presence of the phosphor 8 layer, the LED package 10 combines the radiated light of the LED chip 3 and the radiated light from the phosphor 8 in the sealing resin 4 so as to realize the target color mixing light. It has become. For example, when the LED chip 3 emits blue light, if the sealing resin 4 and the liquid repellent pattern 5 contain a yellow phosphor as the phosphor 8, the yellow phosphor converts the blue light into yellow light. . At this time, when the blue light emitted from the LED chip 3 and the yellow light emitted from the yellow phosphor are combined, white light is synthesized. As a result, white light is emitted from the light emitting surface of the LED chip 3. Thus, the target color mixing light can be obtained by making the sealing resin 4 contain the fluorescent substance 8.

  The liquid repellent pattern 5 is formed so as to surround the LED chip 3 and is in contact with the outer peripheral portion of the sealing resin 4. Specifically, in the present embodiment, the liquid repellent pattern 5 is formed in a ring shape around the LED chip 3. The liquid repellent pattern 5 is formed from a transparent liquid repellent ink, and this liquid repellent ink has a property of being less wettable with respect to the sealing resin 4 than the substrate 1. That is, the liquid repellent pattern 5 has a relatively low affinity for the sealing resin 4. The liquid repellent pattern 5 plays a role of controlling the shape of the sealing resin 4 by utilizing affinity for the sealing resin 4 different from the substrate 1. Thereby, the dispersion | variation in the shape of the sealing resin 4 is suppressed.

  The transparent liquid repellent ink constituting the liquid repellent pattern 5 is not particularly limited as long as the wettability with respect to the sealing resin 4 is lower than that of the substrate 1.

  The planar shape of the liquid repellent pattern 5 is not particularly limited, but is preferably a ring shape as in the present embodiment. Thereby, the surface shape of the sealing resin 4 can be surely made spherical. Further, the amount of the sealing resin 4 used can be minimized, and the cost can be reduced.

  Here, the LED package 10 of this Embodiment can be utilized as a light emitting element array by connecting two or more by the array form. That is, the LED package 10 or an LED array (light emitting element array) in which a plurality of LED packages 10 are connected can be used for various illumination devices such as a backlight mounted on a color liquid crystal display device, for example.

(LED package manufacturing method)
Next, a method for manufacturing the LED package 10 having the above-described configuration will be described with reference to FIGS. 2A, 2 </ b> B, and 2 </ b> C are plan views showing the manufacturing process of the LED package 10.

  In the LED package 10 of this embodiment, after forming the liquid repellent pattern 5 on the substrate 1, the sealing resin 4 is deposited in the liquid repellent pattern 5 and the LED chip 3 is sealed with the sealing resin 4. Can be manufactured.

  First, as shown in FIG. 2A, a substrate 1 having electrodes 2 and 2 is prepared. Next, as shown in FIG. 2B, in the liquid repellent pattern forming step, a transparent liquid repellent ink is applied around the area on the substrate 1 on which the LED chip 3 is mounted, and a ring-shaped liquid repellent is formed. Pattern 5 is formed. At this time, a part of the electrodes 2 and 2 is arranged inside the liquid repellent pattern 5 for connection to the LED chip 3. The liquid repellent pattern forming step can be formed by, for example, flexographic printing.

  Next, as shown in FIG. 2C, the LED chip 3 is mounted on the substrate 1 in the mounting step. That is, after the LED chip 3 is mounted at the center of the substrate 1 in the liquid repellent pattern 5, the LED chip 3 and the electrodes 2 and 2 are connected by the wire 7.

  Thereafter, as shown in FIG. 2C, in the coating process, the sealing resin 4 in which the phosphor 8 is kneaded is applied around the LED chip 3 inside the liquid repellent pattern 5.

  Here, the area where the LED chip 3 is mounted in the liquid repellent pattern 5 is a lyophilic area having high wettability with respect to the sealing resin 4. On the other hand, the liquid repellent pattern 5 is a liquid repellent region having low wettability with respect to the sealing resin 4. Thereby, when the sealing resin 4 is applied around the LED chip 3 in the liquid repellent pattern 5, the sealing resin 4 spreads on the substrate 1 and comes into contact with the inner wall surface of the liquid repellent pattern 5. That is, the liquid repellent pattern 5 blocks the spread of the sealing resin 4. For this reason, if the amount of the sealing resin 4 applied is within the liquid repellent pattern 5, the entire outer edge portion of the sealing resin 4 is in contact with the inner surface of the liquid repellent pattern 5. The application amount of the sealing resin 4 may be such that the sealing resin 4 exceeds the liquid repellent pattern 5 and does not go out of the liquid repellent pattern 5. In this way, as a result of the liquid repellent pattern 5 controlling the spreading of the sealing resin 4, the surface of the cured sealing resin 4 becomes spherical, that is, a convex lens.

  Next, in the present embodiment, the phosphor 8 is allowed to settle in the sealing resin 4 in the sedimentation step.

  By the way, in the LED package 10 which is the final product, the phosphor 8 has a layer distributed with a uniform thickness on the upper surface of the LED chip 3 and the upper surface of the surface of the substrate 1 as shown in FIG. It has become. However, when the thickness of the deposited layer due to the sedimentation of the phosphor 8 is not uniform, variations in chromaticity occur.

  However, when the liquid repellent pattern 5 is used, there is a problem that uniform sedimentation is difficult when the phosphor 8 is sedimented. The cause of this is that the phosphor 8 is precipitated under a temperature condition higher than normal temperature in order to lower the viscosity of the sealing resin 4. In this case, when the oven is used for heating, the sealing resin This is because there is no wall around 4 and it is easily affected by the wind in the oven.

  In the sedimentation process in the oven, for example, as shown in FIG. 3A, the phosphors 8 are unevenly distributed toward the lee. In FIG. 3A, the right side is the windward and the left side is the leeward. Further, as shown in FIG. 3B, when the wind hits from directly above, the deposition amount of the phosphor 8 in the middle decreases and the deposition amount of the phosphor 8 at the end tends to increase. . Further, as shown in FIG. 3C, when the viscosity of the transparent sealing resin 4 is small, the phosphor 8 swells in the central portion where the distribution of the phosphor 8 is large in the dome-shaped sealing resin 4. It is unevenly distributed in shape. The same tendency can be seen when the concentration of the phosphor 8 is low and when the specific gravity of the phosphor 8 is small.

  On the other hand, as shown in FIG. 3D, when the viscosity of the sealing resin 4 is large, sedimentation hardly occurs and chromaticity unevenness increases. Alternatively, there is a problem that the tact time becomes longer even if all sediments. The same tendency can be seen when the concentration of the phosphor 8 or the specific gravity of the phosphor 8 is very low.

  Thus, since the viscosity of the sealing resin 4 decreases as the temperature increases, the sedimentation time can be shortened, and the sedimentation process at the time of temperature rise can shorten the tact. On the other hand, however, there has been a problem that when the use of an oven is affected by wind, the phosphor 8 particles easily move in the lateral direction. That is, in the oven, even if the sedimentation time can be shortened, it is difficult to uniformly sediment the phosphor 8.

  Therefore, in the present embodiment, in the sedimentation step, the phosphor is sedimented in a windless state. In addition, a windless state means the state where the wind speed with respect to the surface of the sealing resin 4 is less than 0.1 m / s.

  In the present embodiment, in the sedimentation step, first, for example, sedimentation is performed for 2 hours and 30 minutes with no wind heating in a 50 ° C. hot plate. The hot plate may be a general hot plate, a stacked hot plate, or a belt conveyor type hot plate. Further, not only hot plates but also lamps such as halogen lamps and infrared lamps can be used. Alternatively, it is possible to perform sedimentation for 4 hours at room temperature and no wind.

  Next, the sealing resin 4 is thermally cured in an oven at 80 ° C. At this time, the wind of the wind speed of 0.1 m / s or more is prevented from directly hitting the surface of the sealing resin 4 by using a weir (not shown). Specifically, in the oven, the entire package of the LED chip 3 can be sealed with a sealed container.

  Thus, the phosphor 8 can be a layer distributed with a uniform thickness on the upper surface of the LED chip 3 and the upper surface of the surface of the substrate 1.

  Here, in this embodiment, when the viscosity condition of the sealing resin 4 in the sedimentation process is the wind speed condition, the sedimentation process is performed in a completely windless state, and the sedimentation time is performed in 1 to 15 hours. Experimentally, it has been confirmed that it is better to determine by the following equation.

Where h: height of the sealing resin, ρ: phosphor specific gravity, ρ _w : sealing resin specific gravity, g: gravitational acceleration, r: phosphor particle radius, η: sealing resin viscosity.

In the above formula, for example, when the specific gravity ρ of the phosphor 8 is 3.2 and the phosphor particle radius r is 15 μm, the sealing resin 4 having a sealing resin specific gravity ρ _w of 1.06. The viscosity η ranges from 1500 cP to 18000 cP.

  Here, the particles of the phosphor 8 fall right below during settling and spread to the surroundings. However, when the viscosity of the settling fluid is low, the ratio of spreading to the surroundings decreases.

  When the particles fall in a liquid having a low viscosity, as shown in FIG. 4, the particles settle in a shape where the center portion is raised compared to the surrounding portion. Assuming that the thickness of the phosphor 8 at the center which is a half point from the outer circumference of the diameter of the sealing resin 4 is A, and the thickness of the phosphor 8 at a quarter point from the outer circumference is B, for example, 45 ° When the sealing resin 4 is applied at the contact angle, the A / B is 1.117 at 500 cP as shown in FIG. As the viscosity increases, the value of A / B approaches 1 and settles parallel to the substrate 1. If the phosphor 8 is in a liquid having a low viscosity, the phosphor 8 settles directly below, so that the thickness ratio of the phosphor layer is equal to the height ratio of the applied sealing resin 4. B is expected to be about 1.3.

  By the way, when there is a height difference between the central portion and the peripheral portion of the phosphor layer, LED characteristics such as chromaticity vary, which causes a problem in quality control. The reason why the variation occurs is as follows.

  For example, when the position of the LED chip 3 varies when the LED chip 3 is die-bonded, if the thickness of the phosphor 8 differs from place to place, there is an individual difference in the amount of the phosphor 8 directly above the LED chip 3. As a result, chromaticity varies. Further, the positional relationship between the LED chip 3 and the phosphor layer may change depending on the application position of the liquid repellent pattern 5.

  For this reason, the process for producing a phosphor layer having a constant thickness as in the LED package 10 of the present embodiment is advantageous in producing an LED package 10 with stable quality by suppressing variations in LED characteristics such as chromaticity. It becomes.

  The actual yield is 99.2% at 1500 cP, compared with 79.2% for the LED package 10 that falls within the chromaticity non-defective range at 500 cP.

  As the viscosity increases, the sedimentation rate decreases, so the productivity becomes poor and cannot be used in the sedimentation process. Therefore, if the sedimentation time of about 15 hours at the maximum is the upper limit, 18000 cP is the upper limit.

  As described above, in the method of manufacturing the LED package 10 according to the present embodiment, the LED package 10 includes the substrate 1, the LED chip 3 mounted on the substrate 1, and the phosphor 8 that seals the LED chip 3. And a sealing resin 4 kneaded. The manufacturing method of the LED package 10 includes a liquid repellent pattern forming process for forming the liquid repellent pattern 5 on the substrate 1, a mounting process for mounting the LED chip 3 inside the liquid repellent pattern 5 on the substrate 1, and the liquid repellent pattern 5. The coating process which apply | coats the sealing resin 4 which knead | mixed the fluorescent substance 8 inside, and the sedimentation process which sediments the fluorescent substance 8 in the sealing resin 4 in a windless state. In addition, the no wind state in a sedimentation process means that the wind speed with respect to the surface of resin is less than 0.1 m / s.

  According to the above method, the liquid repellent pattern forming step for forming the liquid repellent pattern 5 on the substrate 1, the mounting step for mounting the LED chip 3 inside the liquid repellent pattern 5 on the substrate 1, and the inside of the liquid repellent pattern 5 And an application step of applying the sealing resin 4 in which the phosphor 8 is kneaded.

  That is, in the present embodiment, since the sealing resin 4 is molded by the liquid repellent pattern 5, there is no wall in the LED package 10. For this reason, it can avoid that the light extraction efficiency falls because of the wall of the LED package 10.

  Further, since the LED package 10 does not have a recess for the sealing resin, the cost for forming the recess for the sealing resin 4 in the LED package 10 is not required. Therefore, the manufacturing method of the low-cost LED package 10 can be provided.

  Here, when the sealing resin 4 is molded by the liquid repellent pattern 5 using a flat substrate, and the phosphor 8 in the sealing resin 4 is deposited on the upper surface of the LED chip 3 or the like in the sedimentation step, the sealing is performed. When an oven generally used for heating to increase the viscosity of the resin 4 is used, there is no wall around the sealing resin 4, so that the uniform deposition layer of the phosphor 8 is affected by the wind in the oven. It becomes difficult to form.

  Therefore, in the present embodiment, in the sedimentation step, the phosphor 8 in the sealing resin 4 is sedimented in a windless state. As a result, the phosphor 8 can be allowed to settle without being affected by the wind, so that a deposited layer of the phosphor 8 having a constant film thickness can be formed on the upper surface of the LED chip 3 and its periphery.

  Therefore, it is possible to prevent the light extraction efficiency from being lowered due to the wall of the LED package 10 and to make the phosphor 8 kneaded in the sealing resin 4 into a layer uniformly distributed on the LED chip 3 and its periphery. A method for manufacturing the low-cost LED package 10 can be provided.

  In the manufacturing method of the LED package 10 of the present embodiment, the viscosity η of the sealing resin 4 is

However, it is preferable that h: height of the sealing resin, ρ: specific gravity of the phosphor, ρ _w : specific gravity of the sealing resin, g: gravitational acceleration, r: particle radius of the phosphor.

Thus, the sealing resin 4 is kneaded according to the height h of the sealing resin 4, the specific gravity ρ of the phosphor 8, the specific gravity ρ _w of the sealing resin 4, the gravitational acceleration g, and the particle radius r of the phosphor 8. It is possible to set an appropriate condition for the viscosity η of the sealing resin 4 for allowing the formed phosphor 8 to settle and forming a layer evenly distributed on or around the LED chip 3.

  Moreover, in the manufacturing method of the LED package 10 according to the present embodiment, the LED package 10 includes at least one pair of electrodes 2 and 2, one or more LED chips 3, and a die bond that joins the substrate 1 and the LED chip 3. It has a bonding agent 6 and a hemispherical sealing resin 4.

  Thereby, the manufacturing method of LED package 10 provided with the some LED chip 3 can be provided, for example. Further, by making the surface shape of the sealing resin 4 hemispherical, the amount of the sealing resin 4 used can be minimized and the cost can be reduced. Further, by bonding the substrate 1 and the LED chip 3 using the die bond bonding agent 6, for example, by filling the die bond bonding agent 6 up to the side surface of the LED chip 3, the phosphor 8 on the side wall of the LED chip 3. The amount of deposition can be adjusted. Thereby, on the side surface of the LED chip 3, it is possible to prevent the chromaticity variation from occurring due to a step formed in the deposited layer of the phosphor 8 and the LED chip 3 being exposed.

  Moreover, in the manufacturing method of the LED package 10 of the present embodiment, the phosphor 8 has a specific gravity greater than that of the sealing resin 4, and in the sedimentation step, the phosphor 8 settles in the sealing resin 4 due to gravity. That is, for example, as a method for depositing the phosphor 8, sedimentation by weight, centrifugation, adsorption by electromagnetic force, and the like can be considered. However, the method of allowing the sealing resin 4 to settle by gravity is the simplest and leads to low cost.

  In addition, since the amount of the phosphor 8 that settles differs between the end and the center of the sealing resin 4, assuming that the sedimentation proceeds due to the influence of only gravity, the phosphor layer has a cross section at the center and a thick layer at the end. getting thin. However, in reality, this is not the case, and it is considered that conditions such as the viscosity of the sealing resin 4, the specific gravity of the phosphor 8, and the concentration of the phosphor 8 influence the sedimentation process in addition to gravity.

  Moreover, in the manufacturing method of the LED package 10 of this Embodiment, a sedimentation process is performed in the temperature range from 0 degreeC to less than the thermosetting temperature of the sealing resin 4. FIG.

  As a result, the viscosity η of the sealing resin 4 can be adjusted in a temperature range from 0 ° C. to less than the thermosetting temperature of the sealing resin 4, and the sedimentation rate of the phosphor 8 can be appropriately controlled. Become.

  Moreover, in the manufacturing method of the LED package 10 of this Embodiment, it is possible to adjust the temperature of the sealing resin 4 with a lamp | ramp or a hot plate in a sedimentation process. For example, a halogen lamp or an infrared lamp can be used as the lamp. In addition to a general hot plate, a stacked hot plate or a belt conveyor type hot plate can be used as the hot plate.

  Thereby, since an oven is not used, the wind accompanying oven use can be prevented and the uniformity in the deposition layer of the fluorescent substance 8 can be prevented from being lost.

  Moreover, in the manufacturing method of LED package 10 of this Embodiment, it is possible to seal the whole package of LED chip 3 with an airtight container at a sedimentation process.

  Thereby, since the whole package of LED chip 3 is sealed with an airtight container in both sedimentation at normal temperature and sedimentation using an oven, the influence of wind can be avoided.

  Moreover, the LED package 10 of this Embodiment is manufactured using the manufacturing method of the LED package 10 described above.

  This avoids a decrease in light extraction efficiency due to the wall of the LED package 10 and the phosphor 8 kneaded in the sealing resin 4 is uniformly distributed on the LED chip 3 and its periphery. The low-cost LED package 10 can be provided.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIGS. The configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

  The LED package 20 of the present embodiment is replaced by a die bond bonding agent 26 as an element bonding resin as shown in FIG. 7 instead of the configuration of the die bonding bonding agent 6 in the LED package 10 of the first embodiment. Is different from the above.

  That is, in the LED package 20 of the present embodiment, as shown in FIG. 7, the die bond bonding agent 26 that bonds between the LED chip 3 as the light emitting element and the substrate 1 has a slope shape up to the vicinity of the upper surface of the LED chip 3. Is formed.

  As a result, the deposition amount of the peripheral phosphors 8 on the LED chip 3 becomes uniform, which is advantageous for suppressing variation in chromaticity and that the angle dependency of chromaticity is eliminated, that is, from which direction. Also has the advantage of emitting white light.

  That is, in the LED package 10 of the first embodiment, as shown in FIG. 6, the presence of the phosphor 8 is reduced in the vicinity of the upper surface of the side surface of the LED chip 3. As a result, when a blue diode is used as the LED chip 3, blue light is radiated from that portion, so that there is a disadvantage that blue is strong when viewed from an oblique direction.

  In the present embodiment, the drawback can be solved.

  Thus, in the manufacturing method of the LED package 20 according to the present embodiment, the die bond bonding agent 26 is provided so as to be inclined so that the fillet portion on the outer periphery of the LED chip 3 reaches the upper surface of the LED chip 3. Yes.

  Thereby, the phosphor 8 is also deposited on the upper surface of the outer peripheral fillet portion of the LED chip 3. Therefore, on the side surface of the LED chip 3, it is possible to prevent the chromaticity variation from occurring due to a step formed in the deposited layer of the phosphor 8 and the LED chip 3 being exposed.

  Moreover, the LED package 20 of this Embodiment is manufactured using the manufacturing method of the LED package 10 described above.

  This avoids a decrease in light extraction efficiency due to the wall of the LED package 10 and the phosphor 8 kneaded in the sealing resin 4 is uniformly distributed on the LED chip 3 and its periphery. The low-cost LED package 20 can be provided.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the technical means disclosed in different embodiments can be appropriately combined. Such embodiments are also included in the technical scope of the present invention.

  The present invention can be applied to a method for manufacturing a light emitting element package such as an LED, a semiconductor laser, and an organic EL element, and a light emitting element package. And since it can prevent that nonuniformity generate | occur | produces in the brightness | luminance, chromaticity, etc. of light emitting element light, it can apply suitably to the backlight etc. which are used for display apparatuses, such as a lighting fixture and a liquid crystal television.

1 substrate 2 electrode 3 LED chip (light emitting element)
4 Sealing resin 5 Liquid repellent pattern 6 Die bond bonding agent (element bonding resin)
7 Wire 8 Phosphor (wavelength conversion material)
10 LED package (light emitting device package)
20 LED package (light emitting device package)
26 Die bond bonding agent (resin for element bonding)

Claims (9)

In a method for manufacturing a light emitting device package comprising a substrate, a light emitting device mounted on the substrate, and a sealing resin kneaded with a wavelength conversion material for sealing the light emitting device,
A liquid repellent pattern forming step of forming a liquid repellent pattern on the substrate;
A mounting step of mounting a light emitting element inside the liquid repellent pattern on the substrate;
An application step of applying a sealing resin kneaded with the wavelength conversion material inside the liquid repellent pattern;
And a sedimentation step of sedimenting the wavelength conversion material in the sealing resin in a windless state. The viscosity η of the sealing resin is

However, h: height of the sealing resin, ρ: specific gravity of the wavelength conversion material, ρ _w : specific gravity of the sealing resin, g: gravitational acceleration, r: particle radius of the wavelength conversion material. 2. A method for producing a light emitting device package according to 1.   The light emitting element package includes at least one pair of electrodes, one or more light emitting elements, an element bonding resin for bonding the substrate and the light emitting elements, and a hemispherical sealing resin. The method of manufacturing a light emitting device package according to claim 1 or 2.   4. The method of manufacturing a light emitting element package according to claim 3, wherein the element bonding resin is provided so as to be inclined so that a fillet portion of an outer periphery of the light emitting element reaches an upper surface of the light emitting element.   5. The wavelength conversion material according to claim 1, wherein the wavelength conversion material has a higher specific gravity than the sealing resin, and the wavelength conversion material settles in the sealing resin by gravity in the sedimentation step. The manufacturing method of the light emitting element package of description.   The method for manufacturing a light emitting device package according to claim 1, wherein the sedimentation step is performed in a temperature range from 0 ° C. to less than a thermosetting temperature of the sealing resin.   The method of manufacturing a light emitting device package according to claim 1, wherein in the sedimentation step, a temperature of the sealing resin is adjusted by a lamp or a hot plate.   The method for manufacturing a light emitting device package according to claim 1, wherein in the sedimentation step, the entire package of the light emitting device is sealed in a sealed container.   A light emitting device package manufactured using the method for manufacturing a light emitting device package according to claim 1.

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