JP2000252523A - Formation of led - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce color tone variations, etc., caused by uneven filling of the resin containing phosphor by forming a two-stepped recessed section and filling the the resin at least over the upper surface of the lower recessed part. SOLUTION: In a housing of a chip LED, a gallium nitride semiconductor is so formed as to have a lower recessed part 11 for disposing an LED chip 12 and an edge for obtaining the uniformity in the shape of the sealing resin. In other words, the housing is a package formed with a two-stepped recessed section 11, 15. Epoxy resin wherein the phosphor is dispersed is filled into the lower recessed part 11 wherein the LED chip 12 is disposed and then is hardened. The quantity of the resin containing the phosphor is larger than the volume of the lower recessed part 11. When power is supplied to such an LED, the LED chip 12 emits light. By this method, an LED which can emit while light by the mixture of light emitted from the LED chip 12 and light emitted from the phosphor excited by the light emission from the LED chip 12 can be formed with good productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a light emitting diode in which an LED chip disposed in a package is sealed using a phosphor, and more particularly, to a method for determining a light emitting direction of a light emitting diode and an amount of a phosphor. The present invention relates to a method for forming a light emitting diode, which is improved in order to reduce uneven color tone and light emission due to a change in a manufacturing process.

[0002]

2. Description of the Related Art Light-emitting diodes (hereinafter, also referred to as LEDs) are small, efficient, and emit bright colors.
In addition, since it is a semiconductor element, there is no fear of breaking the ball.
It has excellent initial drive characteristics and is resistant to vibration and ON / OFF lighting. Therefore, it is used as various indicators and various light sources. However, LE
Since D has an excellent monochromatic peak wavelength, it is not possible to perform mixed color light emission such as white light in order to improve the efficiency. Therefore, the applicant of the present application has developed a light emitting diode in which light emitted from the blue light emitting diode is color-converted by the phosphor using the blue light emitting diode and the phosphor. Light-emitting diodes using phosphors tend to cause uneven color and uneven brightness due to their characteristics.

Specifically, a light emitting diode emits mixed light of light from a blue LED chip and light from a phosphor that absorbs the light and emits longer-wavelength fluorescent light. Even if there is too much light from the blue LED chip or too much light from the phosphor, the mixed color light may cause color unevenness. In particular, when arranging a phosphor on the LED chip, if the path length of light of the blue LED chip that passes through the phosphor differs depending on the portion, partial color unevenness on the emission observation surface will occur.

In order to eliminate such partial color unevenness and obtain a desired directional angle, the present applicant has disclosed in Japanese Patent Laid-Open No. 10-107.
No. 325 has developed a light emitting diode.
As shown in FIG. 3, a depression is further formed on the bottom surface of the cup so as to reduce the difference in optical path length from the LED chip. LED chip and this LED in the recess narrower than the inside of the cup
By pouring the phosphor-containing resin that covers the chip, the difference in the path length of the light emitted from the LED chip from the recess is reduced. As a result, the difference in the distance that the light emitted from the LED chip passes through the resin containing the phosphor is reduced, and substantially uniform light emission can be achieved.

[0005]

However, at present, strict conditions are imposed on color unevenness and luminance unevenness, for example, as a plurality of light emitting diodes using phosphors are used at the same time as the field of use expands. Instead, further improvements are required. In particular, human tone perception is particularly sensitive in white. Therefore, even a slight difference in color tone is perceived as reddish white, greenish white, yellowish white, or the like. Further, such color unevenness is not only visible, but may not be used in a light emitting diode formed by selecting a color tone or the like according to a specific use such as a sensor. As a result, the yield is greatly reduced. The present applicant has solved the above-mentioned problem and has more uneven color tone,
It is an object of the present invention to provide a method for forming a light-emitting diode which can form a light-emitting diode with less luminance unevenness with a high yield.

[0006]

According to the present invention, there is provided an LED chip disposed on a bottom surface of a base having a concave portion on the surface thereof, and an LED chip disposed on the base.
A mold resin containing a phosphor that converts the wavelength from the D-chip into light of a longer wavelength, wherein the recess is a two-step recess, and the mold resin is disposed at least in the lower step. The present invention relates to a method for forming a light emitting diode in which the LED chip emits visible light and emits mixed color light of the visible light and the fluorescent light from the phosphor while the LED chip emits visible light. is there.

[0007] This makes it possible to reduce uneven color tone and the like, which are caused by non-uniform pouring of the resin containing the phosphor.

[0008]

DETAILED DESCRIPTION OF THE INVENTION As a result of various experiments, the present inventor has found that by forming a specific amount of a mold member having a phosphor in a cup in which LED chips are arranged, it is possible to improve the color tone unevenness of the light emitting diode and improve the yield. The present inventors have found that a high-priced light emitting diode can be used, and have accomplished the present invention.

As shown in FIG. 2A, which is a partially enlarged view of a light emitting diode for comparison with the present invention, the distance that light emitted from an LED chip passes through a phosphor differs in the optical path length due to fluorescent radiation. And the amount of light converted by the phosphor differs. In particular, when the light emitted from the LED chip is narrowed down to suppress color tone unevenness and light emission unevenness, when a recess is provided inside the cup and the LED chip and the phosphor-containing resin are formed in the recess, the manufacturing conditions change over time. The change in the amount of phosphor accompanying the influence significantly affects the path length of light emitted from the LED chip. In particular, when the resin containing the phosphor is poured from the thin tube into the depression, about 0.5 μm
It is a very small amount of about l, and it is extremely difficult to form it with good mass productivity while adjusting the amount. In addition, in order to flow the inside of the thin tube with a resin containing a phosphor, the resin is 3000 CPS.
A relatively low viscosity of the order must be used.
However, the viscosity of the phosphor-containing resin used first in equipment that is continuously mass-produced and that of the phosphor-containing resin after a lapse of time during mass production are slightly different. Therefore, even if a light emitting diode is formed in the same manner, the amount of the phosphor containing resin used for the light emitting diode formed first and the amount of the phosphor containing resin used for the light emitting diode formed later are different. Becomes Such a difference in the amount of the phosphor-containing resin causes a remarkable difference in the distance that the light emitted from the LED chip passes through the resin because the recess is small. Therefore,
In this case, if the amount of the phosphor is adjusted accurately, the mass productivity is reduced. That is, in the past, the reduction in color variation of the light emitting diode and the mass productivity had a relationship of toad-off. In particular, as described above, it was extremely difficult to give priority to the reduction of color variations.

According to the present invention, as shown in the cross-sectional view of FIG. 2B, an edge portion extending outward, for example, is provided at the upper portion of the concave portion for mounting the LED chip inside the package, that is, at least two steps. In the light emitting diode having the concave portion, the amount of the resin is set so that the phosphor-containing resin reaches the widened portion, that is, the upper concave portion. As a result, even if the amount of the resin containing the phosphor fluctuates, the inside of the cup having a relatively large volume such as the upper concave portion is smaller than the inside of the recess having a relatively small volume as shown in FIG. There is little variation in thickness.

Specifically, FIG. 2 (A)
In (B), it is easy to understand if the amount of resin having the same volume is increased or decreased in each case from the respective resin injection set values. First, when the amount of resin of the same volume increases, the resin surface reaches as far as in FIG.
In (B), it was only reached. Next, when the amount of resin of the same volume is reduced, the resin surface is lowered in FIG. 2A and only lowered in FIG. 2B. As shown in FIG. 2, as shown in FIG. 2, although the resin having the same volume fluctuates, the vertical fluctuation of the resin surface position due to the fluctuation is smaller in FIG. 2B. That is, the change in the resin thickness is small. As a result, the variation in the path length difference of the light emitted from the LED chip is small, and a light emitting diode having a desired color tone can be formed with a high yield.

FIG. 1 shows a chip type LED as an example of a specific light emitting diode according to the present invention. The package of the chip type LED is provided with a lower recess in which an LED chip using a gallium nitride-based semiconductor is arranged and an edge portion for making the shape of the sealing resin uniform, that is, a package in which a two-stage recess is formed. ing. An LED chip is fixed in the lower recess using an epoxy resin or the like. A gold wire is used as the conductive wire, and each electrode of the LED chip is electrically connected to each electrode provided on the housing. _{(RE 1-x Sm x)} 3 (Al 1-y Ga y) 5 O 12: Ce
LED with phosphor mixed and dispersed in epoxy resin
It is poured into the lower concave portion where the chip is arranged to be hardened and formed.
The phosphor-containing resin is set so as to flow in a larger amount than the lower recess. By supplying power to such a light emitting diode, the LED chip emits light.
A light-emitting diode capable of emitting white light or the like by mixing colors of light emitted from the LED chip and light emitted from the phosphor excited by the light emission can be formed with high mass productivity.

Hereinafter, the method for forming the light emitting diode of the present invention will be described in more detail, but it goes without saying that the present invention is not limited to this. A GaInN semiconductor having a main emission peak of 470 nm was used as a light emitting element. The LED element is composed of TMG (trimethyl gallium) gas and TMI (trimethyl indium) on a cleaned sapphire substrate.
A gas, a nitrogen gas, and a dopant gas were flowed together with a carrier gas, and a gallium nitride-based compound semiconductor was formed by MOCVD. By switching between SiH ₄ and Cp ₂ Mg as the dopant gas, n
A gallium nitride-based semiconductor having p-type conductivity and a gallium nitride-based semiconductor having p-type conductivity were formed to form a pn junction. (Note that the p-type semiconductor was annealed at 400 ° C. or higher after the film formation.) After exposing the surface of each pn semiconductor by etching, each electrode was formed by sputtering. After a scribe line is drawn on the semiconductor wafer thus completed, the wafer is divided by an external force to obtain a light-emitting device.
A μm square LED element was formed.

On the other hand, after placing a metal piece serving as a lead electrode in a mold, a liquid crystal polymer was injected to form an insert, and after cooling, the package was removed from the mold to form a package member. The package was provided with an opening in the center, and a recess for accommodating the LED element and the mold sealing member was further provided on the bottom of the opening. That is, the concave portions are formed in two steps. An LED element was die-bonded with an epoxy resin in the lower recess. Each electrode of the LED element and the external electrode were wire-bonded with a gold wire to establish electrical continuity.

The phosphor contained in the mold member is
A solution obtained by dissolving rare earth elements of Y, Gd, and Ce in an stoichiometric ratio in an acid was coprecipitated with oxalic acid. This is mixed with a coprecipitated oxide obtained by calcination and aluminum oxide to obtain a mixed raw material. This was mixed with ammonium fluoride as a flux, packed in a crucible, and fired in air at a temperature of 1400 ° C. for 3 hours to obtain a fired product. The calcined product was ball milled in water, washed, separated, dried, and finally formed through a sieve.

(Y _0.4 Gd _0.6 ) ₃ Al ₅ O _{12 formed} :
80 parts by weight of the Ce phosphor and 100 parts by weight of the translucent epoxy resin were mixed well to form a sealing member. The sealing member was injected from the thin tube into the two-step concave portion in the package in which the LED elements were arranged. The injection amount is set so as to sufficiently fill the inside of the lowermost concave portion and to fill the uppermost concave portion. The mold sealing member was cured at 150 ° C. for 5 hours after injection to form a light emitting diode as shown in FIG.

Next, each component of the light emitting diode of the present invention will be described in detail with reference to FIG. (Recesses 11, 15) Of the at least two-stage recesses according to the present invention, the lower recess 11 is for accommodating the LED element 12, and the upper recess 15 has a uniform shape of the injected mold sealing member. And reducing the resin thickness due to a change in the injection amount of the sealing member. Thus, the difference in the path length of the light from the LED element 12 is reduced, and the LED element 12
The light from the phosphor and the light from the phosphor can be sufficiently mixed. That is, the difference in the path length of the light converted from the light of the LED element 12 by the phosphor can be substantially small or extremely small.

The bonding between the LED element 12 and the lower recess 11 can be performed with a thermosetting resin or the like. Specifically, an epoxy resin, an acrylic resin, an imide resin, and the like can be given. The connection between the LED element and the recess 11 is an LED.
Light, ultraviolet light, and the like emitted from the element are also reflected by the fluorescent material and the like, and the density becomes particularly high even in the concave portion 11.
For this reason, it is conceivable that the luminous efficiency is reduced due to yellowing or the like due to deterioration of the resin at the connection portion. In order to prevent such deterioration of the connection portion, it is more preferable to use glass, a resin containing an ultraviolet absorber, or the like for the purpose of preventing deterioration due to ultraviolet rays or the like, or reducing ultraviolet absorption.

Further, the lower recess 11 in which the LED elements are arranged in order to improve the light use efficiency of the light emitting diode.
Alternatively, the surface of the upper recess 15 may be mirror-like, and the surface may have a reflection function. Specifically, as the material of the concave portion, one plated with silver or gold having a high reflectance, copper, copper containing iron,
Examples include tin-containing copper, aluminum alloys, and ceramics with a metallized pattern.

(Phosphor) Next, the phosphor contained in the sealing member filled in the recesses 11 and 15 will be described. The phosphor used in the present invention refers to a phosphor that emits light when excited by at least visible light emitted from a semiconductor light emitting layer. When the light emitted from the LED element 12 using the gallium nitride-based compound semiconductor and the light emitted from the phosphor are in a complementary color relationship or the like, the light from the LED element 12 and the light of the phosphor excited and emitted by the light are respectively When the light corresponds to the three primary colors of light (red, green, and blue), white light emission can be displayed by mixing and displaying light emission from the LED element and light emission from the phosphor. Therefore, it is necessary that light emitted from the LED element 12 and light emitted from the phosphor pass through the mold sealing member outside the light emitting diode. By variously adjusting the ratio of the phosphor to the resin, the application and the filling amount, and by selecting the emission wavelength of the light emitting element, it is possible to provide an arbitrary color tone such as a light bulb color including white.

As the phosphor excited by the semiconductor light emitting layer, various substances such as an inorganic phosphor, an organic phosphor, a fluorescent dye, a fluorescent pigment and the like can be mentioned. Specific phosphor, derivatives of perylene and _{(RE 1-x Sm x)} 3 (Al 1-y G
a _y ) ₅ O ₁₂ : Ce (0 ≦ x <1, 0 ≦ y ≦ 1, provided that R
E is at least one element selected from the group consisting of Y, Gd, and La. ). Particularly phosphor _{(RE 1-x Sm x)} 3 (Al 1-y Ga y) 5 O 12: C
When e is used, it is disposed in contact with or close to the LED element, and has high efficiency and sufficient light resistance even when the irradiance is (Ee) = 3 W · cm ⁻² or more and 10 W · cm ⁻² or less. It can be a diode.

(RE _1-x Sm _x ) ₃ (Al _1-y G _ay )
_{Since the 5} O ₁₂ : Ce phosphor has a garnet structure, it is resistant to heat, light and moisture, and has a peak of an excitation spectrum of 470 nm.
It can be made nearby. The emission peak is 5
A broad emission spectrum that is near 30 nm and extends down to 720 nm can be provided. In addition, the emission wavelength shifts to a short wavelength by substituting a part of the Al in the composition with Ga, and the emission wavelength shifts to a long wavelength by substituting a part of the Y in the composition with Gd. By changing the composition in this way, the emission color can be continuously adjusted. Therefore, there is provided an ideal condition for converting the blue light emission of the nitride semiconductor to white light emission such that the intensity on the long wavelength side can be continuously changed by the composition ratio of Gd.

Also, LE using a gallium nitride based semiconductor
For a light-emitting diode having a D element and a phosphor obtained by adding a rare earth element samarium (Sm) to a yttrium aluminum garnet phosphor (YAG) activated with cerium, the light efficiency is further improved. Can also. Such phosphors include Y, Gd, Ce, S
An oxide or a compound which easily becomes an oxide at a high temperature is used as a raw material of m, Al, La and Ga, and these are sufficiently mixed in a stoichiometric ratio to obtain a raw material. Or Y, Gd, C
e, A solution obtained by dissolving a rare earth element of Sm in an acid at a stoichiometric ratio is coprecipitated with oxalic acid, and a coprecipitated oxide obtained by calcining the mixture is mixed with aluminum oxide and gallium oxide. Get the raw materials. An appropriate amount of a fluoride such as ammonium fluoride is mixed as a flux with the mixture, and the mixture is placed in a crucible.
It can be obtained by calcining in a temperature range of 350 to 1450 ° C. for 2 to 5 hours to obtain a calcined product, then ball-milling the calcined product in water, washing, separating, drying and finally passing through a sieve.

[0024] _{(Y 1-pqr Gd p Ce} q Sm r) 3 Al 5 O 12
Phosphors, in particular, contain Gd in their crystals, so
Excitation emission efficiency in a long wavelength region of 60 nm or more can be increased. Due to the increase in the content of gadolinium, the emission peak wavelength shifts to a longer wavelength from 530 nm to 570 nm, and the entire emission wavelength shifts to the longer wavelength side. When a reddish luminescent color is required, it can be achieved by increasing the substitution amount of Gd. On the other hand, as Gd increases, the emission luminance of blue light gradually decreases. Therefore, p is preferably 0.8 or less, and more preferably 0.7 or less. More preferably, it is 0.6 or less.

Containing Sm (Y _1-pqr Gd _p Ce _q S
The m _r ) ₃ Al ₅ O ₁₂ phosphor has a small decrease in temperature characteristics regardless of an increase in the Gd content. By including Sm in this manner, the emission luminance of the phosphor at a high temperature is greatly improved. The degree of the improvement increases as the content of Gd increases. That is, it was found that a composition in which Gd was increased and the emission color tone of the phosphor was imparted with reddish color was more effective in improving the temperature characteristics by including Sm.
(Note that the temperature characteristic here refers to the excitation light emission luminance at room temperature (25 ° C.) of 450 nm blue light.
It is expressed as a relative value (%) of the emission luminance of the phosphor at a high temperature (200 ° C.). If the content of Sm is in the range of 0.0003 ≦ r ≦ 0.08, the temperature characteristic is preferably 60% or more. When r is smaller than this range, the effect of improving the temperature characteristics is reduced. When r is larger than this range, the temperature characteristic is deteriorated. In the range of 0.0007 ≦ r ≦ 0.02, the temperature characteristic is most preferably 80% or more.

Ce has a relative light emission luminance of 70% or more in the range of 0.003 ≦ q ≦ 0.2. When q is 0.003 or less, the luminance decreases due to the decrease in the number of excitation and emission centers by Ce, and conversely, when it exceeds 0.2, concentration quenching occurs. Specifically, (Y _0.39 Gd _0.57 Ce _0.03 S
m _0.01 ) ₃ Al ₅ O ₁₂ phosphor. In the light emitting diode of the present invention, the phosphor may be a mixture of two or more phosphors. That is, two or more kinds of (RE _1-x S S) having different contents of Al, Ga, Y, La, Gd and Sm.
_{m x) 3 (Al 1-} y Ga y) 5 O 12: Ce phosphor are mixed can increase the RGB wavelength components. By using a color filter, it can be used for a full-color liquid crystal display device.

(LED element 12) L used in the present invention
Examples of the ED element 12 include a nitride-based compound semiconductor capable of efficiently emitting relatively short wavelength light capable of efficiently exciting a phosphor. The LED element which is a light emitting element has M
A semiconductor such as InGaN is formed as a light emitting layer on a substrate by an OCVD method or the like. The structure of the semiconductor is MIS
A homo-structure, hetero-structure or double-hetero structure having a junction, PIN junction, pn junction, or the like can be given. Various emission wavelengths can be selected depending on the material of the semiconductor layer and the degree of mixed crystal thereof. Also, a single quantum well structure or a multiple quantum well structure in which the semiconductor active layer is formed as a thin film in which a quantum effect occurs can be used.

When a gallium nitride compound semiconductor is used, sapphire, spinel, SiC, S
Materials such as i and ZnO are used. In order to form gallium nitride having good crystallinity, a sapphire substrate is preferably used. GaN, AlN on this sapphire substrate
And the like, and a gallium nitride semiconductor having a pn junction is formed thereon. Gallium nitride-based semiconductors exhibit n-type conductivity without being doped with impurities. When a desired n-type gallium nitride semiconductor is formed, for example, to improve luminous efficiency, Si, G
It is preferable to appropriately introduce e, Se, Te, C, and the like.
On the other hand, when forming a p-type gallium nitride semiconductor,
Type dopants Zn, Mg, Be, Ca, Sr, B
a and the like are doped.

Since the gallium nitride-based compound semiconductor is difficult to become p-type only by doping it with a p-type dopant, it is preferable to lower the resistance by introducing a p-type dopant, by heating in a furnace, irradiating a low-speed electron beam, irradiating plasma, or the like. After the exposed surfaces of the p-type semiconductor and the n-type semiconductor are formed by etching or the like, each electrode having a desired shape is formed on the semiconductor layer by a sputtering method, a vacuum evaporation method, or the like.

Next, the formed semiconductor wafer or the like is directly full-cut by a dicing saw in which a blade having a diamond cutting edge is rotated, or after a groove having a width wider than the cutting edge width is cut (half cut). The semiconductor wafer is broken by external force. Alternatively, an extremely thin scribe line (meridian) is drawn on the semiconductor wafer, for example, in a checkerboard pattern by a scriber in which a diamond needle at the tip reciprocates linearly, and then the wafer is cut by an external force and cut into chips from the semiconductor wafer. Thus, the LED element 12 which is a gallium nitride-based compound semiconductor can be formed.

When the light emitting diode of the present invention emits white light, the main emission wavelength of the light emitting device is preferably 400 nm or more and 530 nm or less, more preferably 420 nm or more and 490 nm or less in consideration of the complementary color with the phosphor.
In order to further improve the efficiency of the LED element and the efficiency of the phosphor, the thickness is more preferably 450 nm or more and 475 nm or less.

(Conductive Wire 13) Conductive Wire 1
3, ohmic properties with the electrodes of the LED element 12;
Good mechanical connectivity, electrical conductivity and thermal conductivity are required. The thermal conductivity is 0.01 cal / cm ² /
cm / ° C. or higher, more preferably 0.5 cal
/ Cm ² / cm / ° C. or more. In consideration of workability, the diameter of the conductive wire is preferably Φ10 μm.
m or more and Φ45 μm or less. Specific examples of such conductive wires include conductive wires using metals such as gold, copper, platinum, and aluminum and alloys thereof.

(Mold Sealing Member) The molding member filled in the concave portions 11 and 15 is for protecting the LED element 12, the conductive wire 13 and the like from the outside according to the application of the light emitting diode. The mold member can be formed using various resins, glass, or the like. In addition, the filling amount is set in advance to an amount at least exceeding the upper surface of the lower concave portion in the package in order to obtain a light emitting diode with less color tone unevenness and brightness unevenness.

As a specific material of the molding member, a transparent resin having excellent weather resistance, such as an epoxy resin, a urea resin, or silicone, or glass is preferably used. Also, by incorporating a diffusing agent into the mold member, L
The viewing angle can be increased by relaxing the directivity from the ED element. As a specific material of the diffusing agent, barium titanate, titanium oxide, aluminum oxide, silicon oxide, or the like is suitably used.

(Lead Electrode 14) As the lead electrode,
Since the LED element disposed in the concave portion is electrically connected to the outside of the package, a device having excellent electric conductivity is preferable. Specific examples of the material include metallized nickel or the like or an electric conductor such as phosphor bronze. In addition, the surface of such a material may be plated with silver or gold or the like, and the surface may be used as a light reflecting member so that the light from the LED element as well as the electrode member is efficiently emitted to the outside. it can.

Hereinafter, in order to confirm the effect of the light emitting diode according to the present invention, a light emitting diode as shown in FIG. 3 was formed, and a comparative experiment was performed with the light emitting diode according to the present invention. The light emitting diode of FIG. 3 was formed in the same manner as that of the present invention except that the set value of the amount of the resin containing the phosphor was set on the lowermost surface of the two-step concave portion. Variations in light color between the 1200 light emitting diodes thus formed and 1200 light emitting diodes according to the present invention were observed. The variation within the tolerance of each light emitting diode formed in the method of the present invention was less than about 21% of each light emitting diode of FIG.

Of the 1200 light emitting diodes shown in FIG.
In particular, when the light color variation was conspicuous, the phosphor-containing resin was lower than the surface of the lower recess 31 in the two-stage recess. This is because the set value of the resin injection amount could not be controlled because 1200 pieces were mass-produced. When the amount of resin is larger than the set value, the light emitting diode of FIG. 3 also exerts the same effect as that of the present invention.
3, the effect of providing the two-step concave portions 31 and 35 is lost.

On the other hand, like the light emitting diode of the present invention,
If at least a two-step concave portion is provided, and the set value of the injected resin amount is set in advance to an amount exceeding the lower concave portion, even if the injected resin amount is slightly varied and the resin amount is reduced, Since the resin is prevented from being lower than the surface of the lower concave portion as much as possible, the problem seen in the light emitting diode of FIG. 3 can be avoided as much as possible.

[0039]

According to the present invention, a light emitting diode having at least a two-step recess is provided and the amount of the resin containing the phosphor is set to an amount exceeding the upper surface of the lower recess, whereby the sealing containing the phosphor is achieved. Even if the injection amount of the stop member slightly increases or decreases, it is possible to form a light emitting diode with extremely small color tone deviation, color unevenness, and luminance unevenness with good mass productivity.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a chip type LED which is an example of a light emitting diode of the present invention.

FIG. 2 is a schematic view for explaining an effect of the present invention, and FIG. 2A is a partially enlarged view of a light emitting diode shown for comparison. FIG. 2B is a partially enlarged view of the light emitting diode of the present invention having a two-step concave portion.

FIG. 3 is a schematic sectional view of a light emitting diode shown for comparison with the present invention.

[Explanation of symbols]

 11, 31: the lower concave portion of the stepped concave portion 12, 32: the LED element 13, 33: the conductive wire 14, 34: the lead electrode 15, 35: the stepped concave portion , Upper recess

Claims (2)

[Claims] 1. An LED chip disposed on a bottom surface of a base having a concave portion on a surface, a mold resin containing a phosphor for converting a wavelength from the LED chip into light of a longer wavelength,
A method of forming a light-emitting diode, comprising: an upper edge of an upper portion of the concave portion, the upper portion having an edge-shaped portion extending outward, the at least two-step-shaped concave portion, A method for forming a light-emitting diode, characterized in that the amount of light-emitting diode is filled up to an amount exceeding. 2. The method according to claim 1, wherein the LED chip emits visible light, and the light emitting diode emits mixed color light of visible light from the LED chip and fluorescent light from a phosphor.