JP4122739B2 - Light emitting device and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a light emitting device and a method for manufacturing the same.
[0002]
[Prior art]
  In recent years, LED chips that emit blue light or ultraviolet light using gallium nitride compound semiconductors have been developed. By combining this LED chip with various phosphors, an attempt has been made to develop an LED light emitting device that emits light of a color different from the emission color of the chip, including white. It has advantages such as small size, light weight, and power saving, and is currently widely used as a light source for display, an alternative to a small light bulb, or a light source for a liquid crystal panel.
[0003]
  As a method for forming the phosphor portion in the above-described LED, a method of filling the light-emitting element placement portion with a resin containing a phosphor is common.
[0004]
[Problems to be solved by the invention]
  However, in the above-described prior art, since a small amount of resin containing a phosphor is dropped and filled on each LED mounting portion and cured, there is a problem that the process is complicated and takes time. In addition, it is difficult to control the amount of resin dripping, and furthermore, there is a tendency for the phosphor having a specific gravity to sink within the time when the resin hardens, but the degree of sinking tends to vary. As a result, there is a problem that color variation and light amount variation for each light emitting unit are large.
[0005]
  The present invention has been made in view of the above-mentioned reasons, and its purpose is to manufacture the phosphor part in a simplified process to achieve mass production, to reduce the manufacturing cost, and to improve the phosphor part. An object of the present invention is to provide a light emitting device in which color variations and light amount variations are reduced for each light emitting unit and each product by making the quality uniform, and a method for manufacturing the same.
[0006]
[Means for Solving the Problems]
  According to a first aspect of the present invention, there is provided a light-transmitting substrate, a compound semiconductor that emits light by being stacked on one surface of the light-transmitting substrate, and the compound semiconductor provided on the other surface of the light-transmitting substrate. A layer including at least one of a wavelength conversion material that is excited by the emission of light and emits light having a wavelength different from the excitation wavelength and a light absorber that absorbs part of the light emitted from the compound semiconductor or the wavelength conversion material.Removing the peripheral edge of the other surface side of the translucent substrate to form a first cutting portion, and forming a layer including at least one of the wavelength converting substance and the light absorber in the first cutting Provided in the departmentIt is characterized by that.
[0007]
  According to a second aspect of the present invention, in the first aspect of the invention, the peripheral edge portion of the compound semiconductor and the peripheral edge portion on one surface side of the translucent substrate are removed to form a second cutting portion, and the wavelength A layer including at least one of the conversion substance and the light absorber is provided in the second cutting portion.
[0008]
  The invention of claim 3 is the invention of claim 1 or 2,The wavelength converting substance is made of a phosphor, and the light absorber is made of a pigment or a dye..
[0009]
  The invention of claim 4A wafer is formed by laminating a compound semiconductor that emits light on one surface of the translucent substrate,Furthermore, the peripheral edge part on the other surface side of the translucent substrate is removed to form a first cutting part,On the other surface of the translucent substrateAnd the first cutting partIn addition, at least one of a wavelength conversion material that is excited by light emission of the compound semiconductor and emits light having a wavelength different from the excitation wavelength, and a light absorber that absorbs part of the light emission of the compound semiconductor or wavelength conversion material is used. After forming the layer including the wafer, the wafer is divided into individual elements.
[0010]
  According to a fifth aspect of the present invention, in the wafer according to the fourth aspect, a mesa etch is performed on a peripheral end portion on one surface side of the compound semiconductor and the translucent substrate in the wafer before being divided into individual elements. Forming a cutting portion, forming a layer including at least one of the wavelength converting material and the light absorber on the other surface of the light-transmitting substrate, and dividing the device into individual elements; A face in which an insulating resin including at least one of light absorbers is provided as an adhesive between the element and the mounting substrate by providing the second cutting portion, and the compound semiconductor layer is disposed on the mounting substrate side. It is mounted in a down state.
[0011]
  The invention of claim 6 is the invention of claim 4,In the wafer before being divided into individual elements, a resin in which at least one of the wavelength converting substance and the light absorber is dispersed is applied on the other surface of the light-transmitting substrate, and a spacer is used. Forming a layer containing at least one of the wavelength converting substance and the light absorber by removing the excess resin with a squeegee while controlling the resin to have a constant thickness, and curing the resin. It is characterized by.
[0012]
  The invention of claim 7 is the invention of claim 4,In the wafer before being divided into individual elements, a resin sheet formed of a resin containing at least one of the wavelength converting substance and the light absorber is attached to the other surface of the light-transmitting substrate. To form a layer containing at least one of the wavelength converting substance and the light absorber..
[0013]
  The invention of claim 8 is the invention of claim 4,Forming the resin layer including at least one of the wavelength converting substance and the light absorber on the other surface of the translucent substrate by printing, using the wafer before being cut into individual elements as a base material; Features.
[0014]
  The invention of claim 9 is the invention of claim 7,A resin sheet formed of a transparent resin is used as a base material, and a resin layer including at least one of a wavelength conversion substance and a light absorber is formed on the resin sheet by printing, and then on the other surface of the translucent substrate. The resin sheet is affixed to.
[0015]
  The invention of claim 10 is the invention of claim 8,The printing uses a screen printing method, and a mask is used to apply a resin containing at least one of the wavelength converting substance and the light absorber to a necessary portion on the other surface of the translucent substrate, and an extra portion. A sufficient amount of the resin is removed with a squeegee to form a necessary amount of a resin layer at a required location.
[0016]
  The invention of claim 11 is the invention of claim 9,The printing uses a screen printing method, and a mask is used to apply a resin containing at least one of the wavelength converting substance and the light absorber to a necessary portion on the resin sheet, and an excessive amount of the resin is By removing with a squeegee, a required amount of a resin layer is formed at a required location.
[0017]
  The invention of claim 12 is the invention of claim 8,The printing uses a dot-type printing method of inkjet printing, and a resin containing at least one of the wavelength conversion substance and the light absorber is applied to a necessary portion on the other surface of the translucent substrate using a nozzle. The resin layer is formed by dropping an appropriate amount.
[0018]
  The invention of claim 13 is the invention of claim 9,The printing is performed by using a dot printing method of ink jet printing, and dropping a resin containing at least one of the wavelength converting substance and the light absorber onto a necessary portion on the resin sheet using a nozzle. A layer is formed.
[0019]
  The invention of claim 14 is the invention of claim 10 or 12,The printing is performed by using a multicolor printing technique, and for each location on the other surface of the translucent substrate, the thickness of the resin layer including at least one of the wavelength converting substance and the light absorber, and The wavelength conversion substance dispersed in the resin layer, the type of light absorber, and the concentration are changed.
[0020]
  The invention of claim 15 is the invention of claim 11 or 13,The printing is performed by using a multi-color printing technique, so that the resin layer thickness including at least one of the wavelength converting substance and the light absorber is dispersed in the resin layer for each location on the resin sheet. It is characterized in that the wavelength conversion material, the type of the light absorber, and the concentration are changed.
[0021]
  The invention of claim 16 is the invention of claim 8,The printing uses a photoluminescence technique to spectrally detect the emission intensity of each minute region of the wafer, and based on the result of analysis by a computer, the color unevenness and light amount unevenness for each element are minimized. In addition, the translucent substrate is controlled by a printing method while controlling the thickness of the resin layer including at least one of the wavelength conversion substance and the light absorber, and the type, amount, and concentration of the wavelength conversion substance and the light absorber. The resin layer is formed on the other surface of the film.
[0022]
  The invention of claim 17 is the invention of claim 9,The printing uses a photoluminescence technique to spectrally detect the emission intensity of each minute region of the wafer, and based on the result of analysis by a computer, the color unevenness and light amount unevenness for each element are minimized. In addition, the translucent substrate is controlled by a printing method while controlling the thickness of the resin layer including at least one of the wavelength conversion substance and the light absorber, and the type, amount, and concentration of the wavelength conversion substance and the light absorber. The resin layer is formed on a resin sheet to be affixed on the other surface.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0024]
    (Reference example 1)
  Figure 1 shows the bookReference exampleThe structure of is shown. The translucent substrate 100 is, for example, sapphire or silicon carbide. A compound semiconductor layer made of gallium nitride, gallium nitride / indium, or the like is laminated on one surface, and a pn junction of the n-type semiconductor layer 101 and the p-type semiconductor layer 102 is provided on the surface, and the junction portion. A light emitting diode in which becomes the light emitting layer 103 is formed. In FIG. 1, the p-type semiconductor layer 102 is etched to the n-type semiconductor layer 101, and the n-side electrode 105 is formed on the exposed n-type semiconductor layer 101. The p-side electrode 104 is formed on the p-type semiconductor layer 102. On the other surface of the translucent substrate 100 (the surface opposite to the side where the light emitting diode is formed), a resin 201 in which a phosphor 200 that is a wavelength conversion material is dispersed is applied and bonded. The phosphor 200 is a phosphor that absorbs light emitted from the light emitting diode and emits light of its complementary color. For this purpose, a YAG phosphor or the like can be used. According to this structure, white light can be obtained by mixing the direct light from the light emitting diode and the light converted by the phosphor 200. This element is mounted by a flip chip method in which the electrode side is directly connected to the wiring board.
[0025]
  As an example of the wavelength converting substance, first, the phosphor 200 that emits light of a complementary color of the light emitting diode is cited. However, if phosphors of other emission colors are used, mixed colors other than white can be obtained. If the purpose is to obtain a decorative light source,ShapeA state is also conceivable.
[0026]
  Furthermore, it is also conceivable to use a pigment that is a light absorber instead of the phosphor 200. By using a pigment, it is possible to absorb a specific wavelength and thereby obtain a neutral color. If you want to finely adjust the color tone or obtain a decorative light source,ShapeA state is also conceivable.
[0027]
  If a black pigment is used, the output can be lowered. It can be considered as a method of reducing the output of a bright object when trying to average the output variation of each element. In addition, this method can be used as a method for increasing the contrast when used in a display panel or the like so that the light-off element looks black.
[0028]
  Furthermore, if unevenness is provided on the upper surface of the layer made of the phosphor 200 and the resin 201, it is possible to prevent a decrease in light extraction efficiency due to total reflection. As for this unevenness, the binder resin may be formed in such a shape, or some particles may be mixed therein.
[0029]
    (Reference example2)
  Figure 2 shows the bookReference exampleShows the configuration ofReference example 1The same components as those in FIG.Reference example 1In FIG. 1, the phosphor 200 is dispersed in the resin 201, but here it is dispersed in the glass 202. The glass 202 has higher weather resistance than the resin, and is very unlikely to be discolored by light emitted from the light emitting diode. Further, since it is formed at a relatively high temperature, it is difficult to change even at a high temperature. Accordingly, the light emitting device can withstand use in which a large current flows and a large amount of light and heat is emitted. Therefore, a lighting device having a large light output per element can be obtained.
[0030]
    (Reference example 3)
  Figure 3 shows the bookReference exampleShows the configuration ofReference example 1In the same configuration, the other surface of the translucent substrate 100 (the surface opposite to the side where the light emitting diode is formed) is a non-mirror surface, and fine irregularities are provided. In addition,Reference example 1The same components as those in FIG. Two effects can be obtained by the unevenness of the surface of the translucent substrate 100. One is that the probability that the light transmitted from the translucent substrate 100 side is emitted to the outside without being totally reflected is increased. As a result, the amount of light emitted from the light emitting diode to the outside increases, and the luminous efficiency increases. The other is that the adhesion surface area of the resin 201 fixing the phosphor 200, which is a wavelength converting substance, is increased, so that stronger adhesion can be obtained.
[0031]
  In addition, such a structure facilitates processing and manufacturing in a wafer state in which a compound semiconductor that emits light is laminated on one surface of the translucent substrate 100. The wafer is usually provided with a light-emitting diode comprising an n-type semiconductor layer 101, a p-type semiconductor layer 102, a light-emitting layer 103, a p-side electrode 104, and an n-side electrode 105 on one surface of the translucent substrate 100, and then the final step. It is thinned by lapping (polishing) in the process. Normally, in this step, the polishing is performed by gradually changing from a coarse abrasive to a fine abrasive so as to eliminate surface irregularities. BookReference exampleThen, fine unevenness | corrugation can be obtained by complete | finishing lapping in a comparatively rough grinding | polishing state. Thereafter, a resin 201 in which a phosphor 200 that is a wavelength conversion material is dispersed is applied and bonded to the other surface of the light-transmitting substrate 100. In addition, instead of the phosphor 200, a pigment or a dye that is a light absorber may be used. Further, instead of the resin 201,Reference example 2It is good also as glass 202 similarly to.
[0032]
    (Reference example 4)
  Figure 4 shows the bookReference exampleShows the configuration ofReference example 1The same components as those in FIG. A recess 100a sufficiently larger than the particle size of the phosphor 200 is formed on the other surface of the translucent substrate 100 provided with the phosphor 200 which is a wavelength converting substance (the surface opposite to the side where the light emitting diode is formed). Provide. The shape of the recess 100a is not limited to the inverted triangular groove as shown in FIG. 4, and the same effect can be obtained with any shape. The phosphor 200 is placed in the recess 100a until it reaches the upper portion of the recess 100a, and a translucent resin plate 203 is adhered to form a lid. This provides two effects. One is that the amount and arrangement of the phosphors 200 to be sealed are limited by the shape of the recesses 100a. Thereby, there is no dispersion | variation for every element and it is possible to arrange | position the phosphor 200. FIG. The other is that the phosphor 200 is arranged on the element without using a binding resin. Generally, the binding resin is colored by a photochemical reaction. As a result, the apparent output of the light emitting diode decreases with time. However, in this structure, since no resin is used in the immediate vicinity of the element, such deterioration can be suppressed.
[0033]
  In FIG. 4, the concave portion 100a having the same shape is drawn over the entire area of the element, but it is also conceivable to intentionally change the shape. In general, the amount of light emitted from the peripheral portion and the central portion differs depending on the light emitting element. Further, the light emission distribution also changes due to the influence of the electrodes. It is conceivable to design the shape distribution of the recesses 100a so that the most suitable light is finally emitted in accordance with these light emission states.
[0034]
  In addition, such a structure facilitates processing and manufacturing in a wafer state in which a compound semiconductor that emits light is laminated on one surface of the translucent substrate 100. In general, a wafer is provided with a light-emitting diode including an n-type semiconductor layer 101, a p-type semiconductor layer 102, a light-emitting layer 103, a p-side electrode 104, and an n-side electrode 105 on one surface of a translucent substrate 100, and then individually. It is cut to make a light emitting element. Among these cutting methods, a general method is to provide a groove with a dicing saw in advance, and then divide the entire surface with force. When this split groove is provided, a thick dicing blade is used to provide the groove, and the phosphor 200 is filled there. It is also possible to change the shape of the groove by performing etching after dicing. The groove can be provided by a wire saw other than the dicing blade, etching, laser processing, or the like.
[0035]
    (Reference Example 5)
  SaidReference example 4In this case, a structure in which the phosphor 200 which is a wavelength converting substance is filled using a binding means and a lid such as a translucent resin plate 203 is not used is also conceivable. in this case,Reference example 2The binder having a weather resistance such as the glass 202 described in the above is used. by this,Reference example 4The effect of controlling the amount and arrangement of the phosphor 200 described in the above can be obtained, andReference example 3And substantially the same configuration.
[0036]
  In addition, such a structure facilitates processing and manufacturing in a wafer state in which a compound semiconductor that emits light is laminated on one surface of the translucent substrate 100. In general, a wafer is provided with a light-emitting diode including an n-type semiconductor layer 101, a p-type semiconductor layer 102, a light-emitting layer 103, a p-side electrode 104, and an n-side electrode 105 on one surface of a translucent substrate 100, and then individually. It is cut to make a light emitting element. Among these cutting methods, a general method is to provide a groove with a dicing saw in advance, and then divide the entire surface with force. When providing the split groove, a thick dicing blade is used to provide the groove, and the phosphor 200 and a binder such as glass 202 are filled therein. It is also possible to change the shape of the groove by performing etching after dicing. The groove can be provided by a wire saw other than the dicing blade, etching, laser processing, or the like.
[0037]
    (Embodiment 1)
  FIG. 5 shows the configuration of this embodiment.Reference example 1The same components as those in FIG. Cutting portions 300a and 300b are formed by removing the peripheral end of the other surface (surface opposite to where the light emitting diodes are formed) of the translucent substrate 100 provided with the phosphor 200 which is a wavelength converting substance. The phosphors 200 and the resin 201 are also filled in the cutting parts 300a and 300b. At this time, light emitted from the light emitting diode formed on the other surface of the translucent substrate 100 is emitted not only from the upper surface of the translucent substrate 100 but also from the side surfaces. In order to obtain uniform light, it is necessary to introduce as much light emitted from this side into the phosphor 200 as possible.
[0038]
  This embodiment is a measure for that purpose. The right cutting part 300a in FIG. 5 is formed with the side surfaces inclined, and the left cutting part 300b is formed with the side surfaces perpendicular to the upper surface. Various shapes can be considered for the cutting parts 300a and 300b, and there is no need for any limitation. In addition, although expressed as the cutting portions 300a and 300b, means for actually manufacturing may be etching, etching, and the like, and the method is not limited.
[0039]
  In addition, such a structure facilitates processing and manufacturing in a wafer state in which a compound semiconductor that emits light is laminated on one surface of the translucent substrate 100. In general, a wafer is provided with a light-emitting diode including an n-type semiconductor layer 101, a p-type semiconductor layer 102, a light-emitting layer 103, a p-side electrode 104, and an n-side electrode 105 on one surface of a translucent substrate 100, and then individually. It is cut to make a light emitting element. Among these cutting methods, a general method is to provide a groove with a dicing saw in advance, and then divide the entire surface with force. When this split groove is provided, a thick dicing blade is used, the first groove is provided, phosphor 200 and resin 201 are filled therein, and a second groove is provided at the center with a thin dicing blade. , To reach deeper than the first groove. Then, the structure of this embodiment can be made by applying a force and dividing. It is also possible to change the shape of the groove by performing etching after the first dicing. The groove can be provided by a wire saw other than the dicing blade, etching, laser processing, or the like.
[0040]
    (Embodiment 2)
  FIG. 6 shows the configuration of this embodiment.Embodiment 1The same components as those in FIG. Light generated in the light emitting layer 103 of the light emitting diode is emitted to the n-type semiconductor layer 101 side and the p-type semiconductor layer 102 side, while reflecting between the n-type semiconductor layer 101 and the p-type semiconductor layer 102, There is a significant proportion of lateral propagation. The structure for taking this light into the phosphor 200 is the structure of this embodiment.
[0041]
  FIG. 6 shows the peripheral edge of one surface of the translucent substrate 100 and the peripheral edge of the light emitting diode composed of the n-type semiconductor layer 101, the p-type semiconductor layer 102, the light emitting layer 103, the p-side electrode 104, and the n-side electrode 105. Provided with cutting parts 301a, 301b from which the parts are removed,Embodiment 1In FIG. 5, cutting portions 301 a and 301 b are added.Reference example 1The structure in which the cutting portions 301a and 301b are added to FIG. 1 is also effective.
[0042]
  In FIG. 6, the cutting part 301a on the right side is a case where a groove is formed only by mesa etching. This mesa etching is performed by RIE or the like in order to expose the n-type semiconductor layer 101 and prevent leakage current at the end face. This etching is performed deeper in the periphery of the device so that the width is wider than usual. The portion is filled with a resin 201 in which the phosphor 200 is dispersed.
[0043]
  The left cutting portion 301b is obtained by cutting the translucent substrate 100 with a dicing blade or the like in addition to mesa etching. Also,Embodiment 1Similarly to this, it is possible to make this groove double to make a split groove.
[0044]
    (Reference Example 6)
  Figure 7 shows the bookReference exampleIn the layer including the phosphor 200 and the resin 201, a reflection film (a thin film having a light reflection function) is provided on the surface opposite to the surface facing the translucent substrate 100.Reference example 1The same components as those in FIG.Embodiments 1 and 2, Reference Examples 1 to 5In Japan, it was assumed that the light-emitting element was mounted face-down.Reference exampleSo, it is assumed to be mounted face up. In the face-up, the surface of the reflective film 310 is die-bonded, and the p-side electrode 104 and the n-side electrode 105 are electrically connected to the wiring board by wire bonding. In this case, the surface of the reflective film 310 is the wiring board side. In the absence of the reflective film 310, light is absorbed by the wiring substrate or the die bond agent. In order to avoid this, a reflective film 310 is provided. The reflective film 310 may be a metal thin film or a multilayer film.
[0045]
  In order to manufacture such a structure, an n-type semiconductor layer 101, a p-type semiconductor layer 102, a light emitting layer 103, a p-side electrode 104, and an n-side electrode 105 are formed on one surface of the translucent substrate 100. A method is conceivable in which the reflective film 310 is formed in a wafer state where a light emitting diode is provided and then cut. In this way, the uniform reflective film 310 can be easily formed.
[0046]
    (Reference Example 7)
  Figure 8 shows the bookReference exampleShows the configuration ofReference example 1The same components as those in FIG. A light-emitting diode formed on one surface of the translucent substrate 100, which includes the n-type semiconductor layer 101, the p-type semiconductor layer 102, the light-emitting layer 103, the p-side electrode 104, and the n-side electrode 105, emits ultraviolet rays. As the wavelength converting substance, phosphors 200a, 200b, and 200c that emit blue, green, and red are laminated and used. By mixing these lights, white light is obtained. The color tone can be changed by changing the thickness of each layer of the phosphors 200a, 200b, and 200c of each color.
[0047]
  As the phosphor 200 used here, an optimum one is selected depending on the application, and in order to produce an intermediate color or to adjust the light intensity, a part or all of the layers may contain a pigment or a dye.
[0048]
  In order to manufacture such a structure, a resin sheet in which phosphors 200a, 200b, and 200c are dispersed is formed, and an n-type semiconductor layer 101 and a p-type semiconductor are formed on one surface of the light-transmitting substrate 100. Resin sheet in which phosphors 200a, 200b, and 200c are dispersed on the other surface of the translucent substrate in a wafer state in which a light emitting diode including the layer 102, the light emitting layer 103, the p-side electrode 104, and the n-side electrode 105 is provided. Are stacked and pasted, and then divided into individual elements.
[0049]
    (Reference Example 8)
  Figure 9 shows the bookReference exampleShows the configuration ofReference Example 7The same components as those in FIG. BookReference exampleThe configuration ofReference Example 7The refractive index of the translucent substrate 100 is larger than the refractive index of the sealing material or the air present in the surroundings and the refractive index of each layer of the phosphors 200a, 200b, and 200c. The refractive indexes of the respective layers 200b and 200c are different from each other, and are smaller than the refractive index of the translucent substrate 100, larger than the refractive index of the surrounding sealing material or the atmosphere, and far from the translucent substrate 100. It drops as much. This increases the amount of light emitted from the surface without being totally reflected. Originally, light A that is incident from the light emitting layer 103 to the phosphor layer 200a at a total reflection angle and cannot be emitted to the outside is also radiated from the end face of the phosphor layer 200c, with the optical path being sequentially bent by refraction. . The top surface of the phosphor layer 200c isReference example 1If the surface is rough as described at the end of the above, it is more effective and can be extracted as scattered light B to the outside.
[0050]
    (Reference Example 9)
  FIG.Reference example 1A method for manufacturing a light emitting device having the structure:Reference example 1The same components as those in FIG. A resin 201 in which a phosphor 200 that is a wavelength conversion material is dispersed is applied to the other surface of the wafer having the light emitting layer 103 formed on one surface of the translucent substrate 100 by using a spin coater, and is cured by heat treatment or the like. . The binder may not be the resin 201 but may be glass or the like. Next, this is cut | disconnected by S surface and it is set as each light emitting element. In this way, the resin 201 may be applied before the formation of the light emitting layer 103 or at the final stage of manufacturing the electrodes 104 and 105. In other words, any stage of the process may be used.
[0051]
    (Embodiment 3)
  Reference Example 9In the above, an example using a spin coater has been described, but a method of applying the resin while removing excess resin 201 with a squeegee or the like can be considered. At this time, the thickness is made constant by using a spacer. As the spacer, a method in which a spacer having a certain height is fixed to the wafer in advance and a method in which glass beads 205 having a predetermined diameter are used as shown in FIG. 11 are conceivable. In this case, rather than applying while removing excess resin 201 with a squeegee or the like, a method of pressing the layer of the resin 201 from the upper surface by the pressing means 204 having a flat surface and releasing from the pressing means 204 after curing can be considered.
[0052]
    (Embodiment 4)
  In the present embodiment, in FIG. 10, the light emitting body 200 and the resin 201 are formed in advance from a resin sheet, and a uniform layer can be manufactured by forming the resin sheet in advance. If the resin sheet is provided with irregularities or the distribution and amount of the wavelength converting substance are controlled, the resin sheet can be manufactured separately to facilitate manufacture. Also, it is possible to prepare a plurality of types of resin sheets according to the application, and to bond and assemble them as necessary to continue the manufacturing process.
[0053]
    (Embodiment 5)
  In the present embodiment, a light-emitting diode including an n-type semiconductor layer 101, a p-type semiconductor layer 102, a light-emitting layer 103, a p-side electrode 104, and an n-side electrode 105 is formed on one surface of a translucent substrate 100. A wafer before being cut into elements is used as a base material, and a resin layer containing at least one of a wavelength converting substance and a light absorber is formed on the other surface of the wafer by printing. In any method such as lithographic printing, stencil printing, letterpress printing, intaglio printing, spraying, the wavelength converting substance can be placed on the wafer or a resin plate for the purpose of sticking to the wafer, by making a plate in advance, The feature is that the arrangement of the wavelength converting substance can be finely controlled.
[0054]
  In the light emitting diode, light emission is not uniform due to the arrangement of the electrodes 104, 105, how the light emitting element is cut, the size of the light emitting element, and the like. Therefore, when the wavelength converting substance is arranged, it is effective to arrange according to the light emission characteristics. For example, it is possible to homogenize the intensity distribution of light emitted from the surface of the light emitting element by arranging a black pigment in a portion where a large amount of light is emitted. Alternatively, in order to obtain a uniform white color, it is required to dispose a larger amount of yellow conversion material in the originally strong blue light portion.
[0055]
  In the present embodiment, a patterned wavelength conversion material is disposed on the wafer. This pattern is controlled by the plate. For example, when this pattern is defined as the hole area ratio of the stencil plate, the concentration of the wavelength converting substance per unit area is high in the region where the hole area ratio is high, and is low in the low region. That is, the amount of the wavelength converting substance is controlled not by the amount with respect to the binder or by the ratio of the planar pattern per area, but by the thickness.
[0056]
    (Embodiment 6)
  Embodiment 5In the above description, it is described that the wavelength conversion substance dispersed resin having the same composition and the same concentration is disposed on the wafer by any one method such as lithographic printing, stencil printing, letterpress printing, intaglio printing, and spraying. The present embodiment is a method of further arranging wavelength conversion substance-dispersed resins having different compositions or concentrations in different patterns by using a multicolor printing technique. For example, when the intensity of light and the color of light are homogenized at the same time, it is necessary to arrange phosphors and pigments at a certain ratio at the same time, but this method is possible. When white is obtained by using a phosphor that converts blue light into yellow, the color of white is slightly different due to the slightly different wavelength of blue. In order to make this uniform, it is conceivable to use a plurality of yellow phosphors having different emission peak wavelengths or pigments. In order to easily arrange these at a desired ratio, it is convenient to use a printing method using a multicolor printing technique.
[0057]
    (Embodiment 7)
  Embodiment 6However, as described above, when a white color is obtained using a phosphor that converts blue light into yellow, the white color is slightly different due to the slightly different wavelength of blue. In order to make this uniform, it is conceivable to use a plurality of yellow phosphors having different emission peak wavelengths or pigments. This variation in blue wavelength and intensity occurs within the same wafer. Therefore, in order to correct these, it is more effective to perform each wafer individually than to provide a fixed plate.
[0058]
  The outline is shown in FIG. Using the computer 402, the light detector 401, and the spectroscope 400, the laser light 404 is applied to the wafer 110 from the spectroscope 400 via the lens 403 in advance, that is, the light emission wavelength in the wafer 110 using photoluminescence. And intensity variation are mapped (FIG. 12A). Then, an optimum phosphor coating pattern is calculated from the mapped data, and the phosphor dispersion resin 210 is sprayed onto the wafer 110 or sprayed onto the resin sheet by the ink jet printing system 405 according to this pattern. By adhering this sheet to the wafer 110, the color variation can be corrected (FIG. 12B).
[0059]
【The invention's effect】
  According to a first aspect of the present invention, there is provided a light-transmitting substrate, a compound semiconductor that emits light by being stacked on one surface of the light-transmitting substrate, and the compound semiconductor provided on the other surface of the light-transmitting substrate. A layer including at least one of a wavelength conversion material that is excited by the emission of light and emits light having a wavelength different from the excitation wavelength and a light absorber that absorbs part of the light emitted from the compound semiconductor or the wavelength conversion material.Removing the peripheral edge of the other surface side of the translucent substrate to form a first cutting portion, and forming a layer including at least one of the wavelength converting substance and the light absorber in the first cutting Provided in the departmentTherefore, there is an effect that the wavelength converting substance and the light absorber can be formed uniformly and with less variation between lots.Furthermore, the light emitted in the lateral direction of the element can be partially guided to the wavelength conversion substance and the light absorber, and there is an effect that the light use efficiency is improved and the color is improved.
[0060]
  According to a second aspect of the present invention, in the first aspect of the invention, the peripheral edge portion of the compound semiconductor and the peripheral edge portion on one surface side of the translucent substrate are removed to form a second cutting portion, and the wavelength Since the layer containing at least one of the conversion substance and the light absorber is provided in the second cutting portion, the same effect as in the first aspect can be obtained, and the light extraction efficiency in the lateral direction of the element can be improved. There is.
[0061]
  The invention of claim 3 is the invention of claim 1 or 2,Since the wavelength converting substance is made of a phosphor and the light absorber is made of a pigment or a dye, the same effect as in claim 1 can be obtained by using the phosphor, the pigment and the dye..
[0062]
  The invention of claim 4A wafer is formed by laminating a compound semiconductor that emits light on one surface of the translucent substrate,Furthermore, the peripheral edge part on the other surface side of the translucent substrate is removed to form a first cutting part,On the other surface of the translucent substrateAnd the first cutting partIn addition, at least one of a wavelength conversion material that is excited by light emission of the compound semiconductor and emits light having a wavelength different from the excitation wavelength, and a light absorber that absorbs part of the light emission of the compound semiconductor or wavelength conversion material is used. Since the wafer is divided into individual elements after forming the layer including the effect, it is possible to easily make uniform light-emitting elements in a lump compared to the conventional process for each element. There is.Furthermore, there is an effect that light emitted in the lateral direction of the element can be partially guided to the wavelength conversion substance and the light absorber, and a light emitting element with good light use efficiency and good color can be produced.
[0063]
  According to a fifth aspect of the present invention, in the wafer according to the fourth aspect, a mesa etch is performed on a peripheral end portion on one surface side of the compound semiconductor and the translucent substrate in the wafer before being divided into individual elements. Forming a cutting portion, forming a layer including at least one of the wavelength converting material and the light absorber on the other surface of the light-transmitting substrate, and dividing the device into individual elements; A face in which an insulating resin including at least one of light absorbers is provided as an adhesive between the element and the mounting substrate by providing the second cutting portion, and the compound semiconductor layer is disposed on the mounting substrate side. Since it is mounted in the down state, the same effect as in claim 4 can be obtained, and further, a light emitting element having a high light extraction efficiency in the lateral direction of the element can be produced.
[0064]
  The invention of claim 6 is the invention of claim 4,In the wafer before being divided into individual elements, a resin in which at least one of the wavelength converting substance and the light absorber is dispersed is applied on the other surface of the light-transmitting substrate, and a spacer is used. Since the resin is controlled so as to have a certain thickness, the excess resin is removed with a squeegee to form a layer containing at least one of the wavelength converting substance and the light absorber and cured. There is an effect that a light-emitting element having a layer having a uniform film thickness can be easily produced.
[0065]
  The invention of claim 7 is the invention of claim 4,In the wafer before being divided into individual elements, a resin sheet formed of a resin containing at least one of the wavelength converting substance and the light absorber is attached to the other surface of the light-transmitting substrate. To form a layer containing at least one of the wavelength converting substance and the light absorber, so that a sheet is prepared in advance, and a large number of homogeneous and high-quality sheets can be prepared by a processing method most suitable for making the sheet. There is an effect.
[0066]
  The invention of claim 8 is the invention of claim 4,Since the wafer before being cut into individual elements is used as a base material, and a resin layer including at least one of the wavelength converting substance and the light absorber is formed on the other surface of the translucent substrate by printing, There is an effect that it is possible to make a light-emitting element having fine reproducibility while finely controlling the distribution of the wavelength converting substance and the light absorber. According to this method, it is naturally possible to form the same conditions, but it is also easy to provide a difference in concentration and amount. As a result, preferable color tone, light distribution, etc. There is an effect that can be obtained.
[0067]
  The invention of claim 9 is the invention of claim 7,A resin sheet formed of a transparent resin is used as a base material, and a resin layer including at least one of a wavelength conversion substance and a light absorber is formed on the resin sheet by printing, and then on the other surface of the translucent substrate. Since the resin sheet is attached to the sheet, it is possible to prepare a large number of homogeneous and high-quality sheets in advance by making the sheet in advance, and using the most suitable processing method for making the sheet, and the wavelength converting substance and light absorber. There is an effect that it is possible to manufacture a light-emitting element with fine distribution control and high reproducibility. According to this method, it is naturally possible to form the same conditions, but it is also easy to provide a difference in concentration and amount. As a result, preferable color tone, light distribution, etc. There is an effect that can be obtained.
[0068]
  The invention of claim 10 is the invention of claim 8,The printing uses a screen printing method, and a mask is used to apply a resin containing at least one of the wavelength converting substance and the light absorber to a necessary portion on the other surface of the translucent substrate, and an extra portion. By removing a sufficient amount of the resin with a squeegee, a required amount of the resin layer was formed at the required location. Therefore, a light emitting device provided with a layer of wavelength converting material and light absorber having substantially the same thickness was very easily provided. There is an effect that it can be made.
[0069]
  The invention of claim 11 is the invention of claim 9,The printing uses a screen printing method, and a mask is used to apply a resin containing at least one of the wavelength converting substance and the light absorber to a necessary portion on the resin sheet, and an excessive amount of the resin is By removing with a squeegee, a necessary amount of the resin layer is formed at a necessary location, and thus the same effect as in the tenth aspect can be achieved.
[0070]
  The invention of claim 12 is the invention of claim 8,The printing uses a dot-type printing method of inkjet printing, and a resin containing at least one of the wavelength conversion substance and the light absorber is applied to a necessary portion on the other surface of the translucent substrate using a nozzle. Since the resin layer is formed by dropping an appropriate amount, there is an effect that it is possible to make a light emitting element in which the arrangement and amount of the wavelength converting substance and the light absorber are freely controlled.
[0071]
  The invention of claim 13 is the invention of claim 9,The printing is performed by using a dot printing method of ink jet printing, and dropping a resin containing at least one of the wavelength converting substance and the light absorber onto a necessary portion on the resin sheet using a nozzle. Since the layer is formed, the same effect as that of claim 12 is obtained.
[0072]
  The invention of claim 14 is the invention of claim 10 or 12,The printing is performed by using a multicolor printing technique, and for each location on the other surface of the translucent substrate, the thickness of the resin layer including at least one of the wavelength converting substance and the light absorber, and Since the wavelength conversion material and the type and concentration of the light absorber dispersed in the resin layer are changed, a light emitting device using a plurality of wavelength conversion materials and light absorbers and freely changing the ratio thereof There is an effect that can be made.
[0073]
  The invention of claim 15 is the invention of claim 11 or 13,The printing is performed by using a multi-color printing technique, so that the resin layer thickness including at least one of the wavelength converting substance and the light absorber is dispersed in the resin layer for each location on the resin sheet. Since the wavelength conversion material, the type of the light absorber, and the concentration are changed, the same effect as in the 14th aspect can be obtained.
[0074]
  The invention of claim 16 is the invention of claim 8,The printing uses a photoluminescence method to spectrally detect the emission intensity of each minute region of the wafer, and based on the result of analysis by a computer, color unevenness and light amount unevenness for each element are minimized. In addition, the translucent substrate is controlled by a printing method while controlling the thickness of the resin layer including at least one of the wavelength conversion substance and the light absorber, and the type, amount, and concentration of the wavelength conversion substance and the light absorber. Since the resin layer is formed on the other side of the light-emitting element, even in a light-emitting element made on the same wafer, the brightness and color are different depending on the location, but this is a pattern that measures and corrects this in advance. As a whole, there is an effect that a very uniform light emitting element can be manufactured by arranging the wavelength converting substance and the light absorber.
[0075]
  The invention of claim 17 is the invention of claim 9,The printing uses a photoluminescence method to spectrally detect the emission intensity of each minute region of the wafer, and based on the result of analysis by a computer, color unevenness and light amount unevenness for each element are minimized. In addition, the translucent substrate is controlled by a printing method while controlling the thickness of the resin layer including at least one of the wavelength conversion substance and the light absorber, and the type, amount, and concentration of the wavelength conversion substance and the light absorber. Since the said resin layer was formed on the resin sheet affixed on the other surface of this, there exists an effect similar to Claim 16.
[Brief description of the drawings]
FIG. 1 of the present inventionReference example 1FIG.
FIG. 2 of the present inventionReference example 2FIG.
FIG. 3 of the present inventionReference example 3FIG.
FIG. 4 of the present inventionReference example 4FIG.
FIG. 5 shows the present invention.Embodiment 1FIG.
FIG. 6 of the present inventionEmbodiment 2FIG.
[Fig. 7] of the present invention.Reference Example 6FIG.
[Fig. 8] of the present inventionReference Example 7FIG.
FIG. 9 shows the present invention.Reference Example 8FIG.
FIG. 10 shows the present invention.Reference Example 9FIG.
FIG. 11 shows the present invention.Embodiment 3FIG.
FIG. 12 shows the present invention.Embodiment 7FIG.
[Explanation of symbols]
  100 Translucent substrate
  101 n-type semiconductor layer
  102 p-type semiconductor layer
  103 Light emitting layer
  104 p-side electrode
  105 n-side electrode
  200 phosphor
  201 resin

Claims (17)

A translucent substrate, a compound semiconductor that is stacked on one surface of the translucent substrate and emits light, and is provided on the other surface of the translucent substrate and excited by light emission of the compound semiconductor. A layer including at least one of a wavelength conversion material that emits light having a wavelength different from the wavelength and a light absorber that absorbs part of light emitted from the compound semiconductor or the wavelength conversion material, and the other of the light- transmitting substrate. A first cutting portion is formed by removing a peripheral end portion on the surface side of the surface, and a layer including at least one of the wavelength converting substance and the light absorber is provided in the first cutting portion. Light emitting element. A layer including at least one of the wavelength converting material and the light absorber by removing the peripheral end of the compound semiconductor and the peripheral end on one side of the translucent substrate to form a second cutting portion. The light emitting device according to claim 1, wherein the second cutting portion is provided. The light emitting device according to claim 1, wherein the wavelength converting substance is made of a phosphor, and the light absorber is made of a pigment or a dye. A compound semiconductor that emits light is laminated on one surface of the translucent substrate to form a wafer, and the peripheral end portion on the other surface side of the translucent substrate is removed to form a first cutting portion. A wavelength converting substance that is excited by light emission of the compound semiconductor and emits light having a wavelength different from the excitation wavelength on the other surface of the translucent substrate and the first cutting portion, and the compound semiconductor or A method for manufacturing a light-emitting element, comprising: forming a layer including at least one of a light absorber that absorbs part of light emitted from a wavelength converting substance, and then dividing the wafer into individual elements. In the wafer before being divided into individual elements, a mesa etch is applied to a peripheral end portion on one surface side of the compound semiconductor and the translucent substrate to form a second cutting portion, and the translucent substrate An insulating layer including at least one of the wavelength converting material and the light absorber after forming a layer including at least one of the wavelength converting material and the light absorber on the other surface and dividing into individual elements. The resin is used as an adhesive between the element and the mounting substrate by providing the resin in the second cutting portion, and the compound semiconductor layer is mounted in a face-down state in which the layer is disposed on the mounting substrate side. 4. A method for producing a light-emitting device according to 4. In the wafer before being divided into individual elements, a resin in which at least one of the wavelength converting substance and the light absorber is dispersed is applied on the other surface of the light-transmitting substrate, and a spacer is used. Forming a layer containing at least one of the wavelength converting substance and the light absorber by removing the excess resin with a squeegee while controlling the resin to have a constant thickness, and curing the resin. The method for manufacturing a light-emitting element according to claim 4. In the wafer before being divided into individual elements, a resin sheet formed of a resin containing at least one of the wavelength converting substance and the light absorber is attached to the other surface of the light-transmitting substrate. 5. The method of manufacturing a light emitting device according to claim 4, wherein a layer including at least one of the wavelength converting substance and the light absorber is formed. Forming the resin layer including at least one of the wavelength converting substance and the light absorber on the other surface of the translucent substrate by printing, using the wafer before being cut into individual elements as a base material; The method for manufacturing a light-emitting element according to claim 4. A resin sheet formed of a transparent resin is used as a base material, and a resin layer including at least one of a wavelength conversion substance and a light absorber is formed on the resin sheet by printing, and then on the other surface of the translucent substrate. The method for manufacturing a light-emitting element according to claim 7, wherein the resin sheet is attached to the substrate. The printing uses a screen printing method, and a mask is used to apply a resin containing at least one of the wavelength converting substance and the light absorber to a necessary portion on the other surface of the translucent substrate, and an extra portion. 9. The method of manufacturing a light-emitting element according to claim 8, wherein a required amount of the resin layer is formed at a required location by removing a sufficient amount of the resin with a squeegee. The printing uses a screen printing method, and a mask is used to apply a resin containing at least one of the wavelength converting substance and the light absorber to a necessary portion on the resin sheet, and an excessive amount of the resin is The method for manufacturing a light-emitting element according to claim 9, wherein a necessary amount of a resin layer is formed at a necessary location by removing the squeegee. The printing uses a dot-type printing method of inkjet printing, and a resin containing at least one of the wavelength conversion substance and the light absorber is applied to a necessary portion on the other surface of the translucent substrate using a nozzle. The method for producing a light-emitting element according to claim 8, wherein the resin layer is formed by dropping an appropriate amount. The printing is performed by using a dot printing method of ink jet printing, and dropping a resin containing at least one of the wavelength converting substance and the light absorber onto a necessary portion on the resin sheet using a nozzle. The method for manufacturing a light-emitting element according to claim 9, wherein a layer is formed. The printing is performed by using a multicolor printing technique, and for each location on the other surface of the translucent substrate, the thickness of the resin layer including at least one of the wavelength converting substance and the light absorber, and 13. The method for manufacturing a light-emitting element according to claim 10, wherein the wavelength conversion substance dispersed in the resin layer, the type of light absorber, and the concentration are varied. The printing is performed by using a multi-color printing technique, so that the resin layer thickness including at least one of the wavelength converting substance and the light absorber is dispersed in the resin layer for each location on the resin sheet. 14. The method for manufacturing a light-emitting element according to claim 11, wherein the wavelength conversion substance, the type of the light absorber, and the concentration are varied. The printing uses a photoluminescence technique to spectrally detect the emission intensity of each minute region of the wafer, and based on the result of analysis by a computer, the color unevenness and light amount unevenness for each element are minimized. In addition, the translucent substrate is controlled by a printing method while controlling the thickness of the resin layer including at least one of the wavelength conversion substance and the light absorber, and the type, amount, and concentration of the wavelength conversion substance and the light absorber. The method for manufacturing a light emitting device according to claim 8, wherein the resin layer is formed on the other surface of the light emitting device. The printing uses a photoluminescence technique to spectrally detect the emission intensity of each minute region of the wafer, and based on the result of analysis by a computer, the color unevenness and light amount unevenness for each element are minimized. In addition, the translucent substrate is controlled by a printing method while controlling the thickness of the resin layer including at least one of the wavelength conversion substance and the light absorber, and the type, amount, and concentration of the wavelength conversion substance and the light absorber. The method for manufacturing a light-emitting element according to claim 9, wherein the resin layer is formed on a resin sheet to be attached to the other surface of the substrate.

Images