KR20080090062A - Light emitting diode package and manufacturing method thereof, surface light emitting apparatus - Google Patents

Abstract

A light-emitting diode package, a manufacturing method thereof and a surface light-emitting device are provided to improve center luminous intensity by increasing light reflectivity inside a cavity of a package body through a metal thin film formed an inner surface or outer surface of the cavity. A light-emitting diode package includes a package body(110), an inner metal thin film(112), outer metal thin films(114,116,118) and a light-emitting diode(130). A cavity(120) is formed in the package body. The inner metal thin film is formed inside the cavity to be electrically opened. The outer metal thin films are connected to the inner metal thin film and are formed on an outer surface of the package body. The light-emitting diode is mounted on the inner metal thin film of the cavity. The package body uses one of polymer material, resin material and ceramic material. The outer metal thin films includes a front metal thin film formed in front of the package body, and side metal thin films formed in right and left sides of the package body to be connected to the front metal thin film.

Description

Light emitting diode package and manufacturing method thereof, surface light emitting device

1 is a cross-sectional view of a conventional light emitting diode package.

Figure 2 is a side perspective view of a light emitting diode package according to an embodiment of the present invention.

3 is a rear perspective view of FIG. 2;

(A) (b) is a side sectional view of Y-Y, X-X of FIG.

5 is a perspective view showing an example in which the mold member is molded in the cavity in the LED package according to the present invention.

Figure 6 is a view showing a solder bonding example of a light emitting diode package according to the present invention.

7 and 8 are a perspective view and a front view showing an example of the plating of the top surface of the metal thin film of the present invention.

9 is a view showing a light emitting diode package manufacturing process example according to an embodiment of the present invention.

 <Explanation of symbols for main parts of the drawings>

100: light emitting diode package 110: package body

120: cavity 111: metal thin film

112: inner metal thin film 114, 114a, 114b, 116,118: outer metal thin film

130: light emitting diode 140: mold member

The present invention relates to a light emitting diode package, a method of manufacturing the same, and a surface light emitting device having the same.

Today, there is provided a light emitting device having a semiconductor element represented by a light emitting element or a light receiving element, and a support having a lead frame which protects the light emitting element or the light receiving element from an external environment and connects these electrodes.

In particular, as a light emitting device, a light emitting diode capable of emitting white mixed color light with high luminance by combining the light emitting element and a phosphor that absorbs light from the light emitting element and emits light having different wavelengths has been developed. A light source using such a light emitting diode is used in various fields.

In addition, a light emitting diode is fixed to a support called a package and used as a light emitting device. For example, the surface mount type light emitting device which can irradiate light in the direction substantially parallel to the element mounting area of a light emitting device is mentioned.

1 is a cross-sectional view showing a conventional LED package.

Referring to FIG. 1, the light emitting diode package 10 includes a silver plated lead frame 31 protruding from both sides of the package body 11, and a cavity 12 formed of a narrow and long groove by injection molding. Is formed.

In addition, after the light emitting diode 20 is attached to the inside of the cavity 12 in the form of a chip and bonding the wire 21, the mold member 16 is formed by filling and curing a liquid transparent resin. The mold member 16 mainly uses an epoxy or silicon material, and in some cases, phosphor powder may be added.

The amount and distribution of phosphors in the mold member 16 determine the color coordinates of the white light, and the injection-molded cavity 12 basically spreads the light emitted from the light emitting diodes 20 in a thin and wide manner. The light emitting diode package is a side mount package and is surface mounted to the backlight unit.

However, as the package body 11 made of PPA becomes thinner (about 70um or less), part of the light generated from the light emitting diode is transmitted through the side surface of the package body made of PPA material, resulting in light loss.

In addition, since the lead frame is formed, the plating thereof, and the injection molding process are performed, the manufacturing process is complicated.

The present invention provides a light emitting diode package and a surface light emitting device having the same.

The present invention provides a light emitting diode package and a method of manufacturing the same, which form a metal thin film on the inside and outside of the cavity to perform a role of reflecting light and an electrode in the cavity.

A light emitting diode package according to an embodiment of the present invention, the cavity body is formed; An inner metal thin film electrically open and formed inside the cavity; An outer metal thin film connected to the inner metal thin film and formed on an outer surface of the package body; It includes a light emitting diode mounted on the inner metal thin film of the cavity.

Method of manufacturing a light emitting diode package according to an embodiment of the present invention comprises the steps of forming a cavity on the front of the package body; Forming an electrically open area in the cavity and in front of the package body; Forming a metal thin film on the inside of the cavity, the front surface of the package body, and the left and right sides of the package body; And mounting a light emitting diode inside the cavity having the electrically open area.

Hereinafter, a light emitting diode package and a method of manufacturing the same according to the present invention will be described with reference to the accompanying drawings.

2 is a front perspective view of the LED package according to an embodiment of the present invention, Figure 3 is a rear perspective view of Figure 2, Figure 4 (a) (b) is a side cross-sectional view seen from X-X and Y-Y of FIG.

2 to 4, the light emitting diode package 100 is a side emitting type or top emitting type package product, which is formed in a polyhedral shape, and is various as a surface light emitting device such as a light source for a backlight and an illumination field of a liquid crystal display device. Can be applied. Hereinafter, a side light emitting diode package will be described for convenience of description.

The light emitting diode package 100 includes a package body 110 having a cavity, metal thin films 111: 112, 114, 116 and 118, and a light emitting diode 130 as a semiconductor device.

The package body 110 may be a polymer material such as polyphthalamide (PPA), a liquid crystal polymer (LCP), and syndiotactic polystyrene (SPS), a ceramic material of alumina (Al ₂ O ₃ ) and AlN, and a resin such as silicon. Materials may be optionally used.

The package body 110 is formed in a polyhedral shape, the cavity 120 is formed to a predetermined depth (for example 200 ~ 400um). Here, the shape of the polyhedron may not necessarily be formed only as a surface, and may partially include a curved surface.

Here, when the structure of the package main body 110 is shown, the direction in which the length of the cavity is long becomes the long axis of the package main body, and the direction in which the length of the cavity is short is the shortening of the package main body.

The surface on which the cavity 120 is formed is the front surface of the package body, and the opposite surface opposite to the front surface of the package body is the rear surface 103 of the package body. The surface on which the package body is mounted is the upper surface 101 or the lower surface 102 of the package body. Two side surfaces positioned between the front and rear surfaces of the package body and between the upper and lower surfaces thereof and facing each other are the left and right surfaces of the package body.

The metal thin film 111 is an inner metal thin film 112 formed inside the cavity 120, and an outer metal extending on the inner metal thin film 112 and formed on the front and left / right surfaces of the package body 100. Thin film 114,116,118.

In addition, as shown in FIG. 3, the metal thin film 111 may include a rear metal thin film 118 extending to a portion of the rear surface of the package body. Since the metal thin film 111 extends from the inside of the cavity to the outside, it may be used as a heat dissipation path.

The inner metal thin film 112 is formed on an inner bottom surface and an inclined surface of the cavity 120, and the inner metal thin film 112 is divided into two electrode regions by the nonmetal part 122. The non-metal part 122 is formed to the inner bottom surface and the inclined surface of the cavity 120 and the top surface of the cavity 120 to be electrically open for the electrode functions of the inner and outer metal thin films 112 and 114. It is an area to let you. The internal metal thin film 112 serves as a reflection and electrode of light generated from the light emitting diode 130 and is formed to a predetermined thickness.

The outer metal thin films 114, 116 and 118 may be formed of the front metal thin film 114 formed on the front surface of the package body 110, the side metal thin film 116 formed on the left and right surfaces of the package body 110, and the package body 110. The back metal thin film 118 formed on the back surface is electrically connected.

Here, as another example, a groove (not shown) such as a concave shape or a concave lens is formed on a part or all of at least one side of the front, left / right, and rear surfaces of the package main body 110 from the surface of the package main body 110. It is also possible to form external metal thin films in the grooves, respectively. For example, the front metal thin film 114 may be formed by forming a groove in a part or all of the front surface of the package body 110 in the long axis direction. In this manner, the side metal thin film 116 and / or the back metal thin film 118 may also be formed in the groove formed in the surface thereof. In this case, the surface of the package body 110 and the surface of the outer metal thin film formed in the groove may be located on the same plane.

The metal thin film 111 may be formed in a range of 1 to 22 μm by containing a metal material having good reflection characteristics by using a method such as sputtering, deposition, electroplating, electroless plating, or coating. For example, the metal thin film 111 may be stacked in the order of an adhesion layer and a reflection layer, and the adhesion layer may be omitted and a reflective layer may be immediately formed. In addition, a thin film protective layer may be partially formed on the entire surface of the package body 110 in which the metal thin film is formed. In addition, the adhesive layer may be formed in several hundreds of kPa or more to 2um or less by plating under the use of one or more materials such as Ni, Ti, Cr, Cu, etc., and the reflective layer is electrolytic or electroless plating using one or more Ag or Al materials. It may be formed in 1 ~ 20um and the like.

Here, the inner metal thin film 112 formed in the cavity 120 may have a reflectance of 95% or more by the reflective layer, thereby improving the center luminous intensity and heat emission efficiency effect.

The cavity 120 is inclined in an angle θ1 and θ2 of the inclined surfaces 113b and 113c with respect to the cavity bottom surface 113a as shown in (a) and (b) of FIG. 4 in the range of 90 ° to 120 °. Therefore, the light extraction effect can be improved.

The light emitting diode 130 is mounted in the form of a semiconductor chip in the cavity 120 in which the metal thin film 111 is formed. In addition, a protection device such as a zener diode may be mounted in the cavity 120 to protect the light emitting diode 130.

The light emitting diode 130 may be mounted on the inner metal thin film 112 of the cavity 120 in a manner such as wire 131 bonding and / or flip chip bonding. npn junction structure. In addition, the cavity 120 may include at least one of AlGaN-based, GaN-based, InGaAlP, and GaAs-based semiconductor light emitting devices.

Alternatively, the light emitting diode 130 may be implemented as a white light emitting diode using an LED chip and a phosphor (eg, a silicate-based phosphor), or a red LED chip, a green LED chip, a blue LED chip, a yellow green LED chip, and a white LED. It may also be configured as a package in which one or more chips are combined.

As shown in FIG. 5, after the light emitting diode 130 is mounted in the cavity 120, the mold member 140 is molded into the area, and the molding member 140 is made of transparent resin such as epoxy or silicon. Is discharged into the cavity 120 and undergoes a curing process.

In this case, the mold member 140 may be molded by mixing phosphor (eg, silicate-based phosphor) powder. The molding member 140 may selectively use a molding liquid or an additive depending on the purpose of use, the environment of use, and the characteristics of the product.

The mold member 140 may have a flat shape, the surface of which is molded at the same height as the top of the cavity 120, a concave lens shape concave with respect to the top of the cavity 120, or convex with respect to the top of the cavity 120. It may be formed in any one of the lens form.

6 is a cross-sectional view illustrating a structure in which the package body 110 is bonded.

Referring to FIG. 6, the side metal thin film 116 of the package body 110 includes upper and lower inclined surfaces 116b and 116c that are inclined at an angle with respect to the upper and lower surfaces of the package body 110. Here, the lower inclined surface 116c is formed at an angle θ3 of 120 ° to 150 ° based on the lower surface 102 of the package body 110.

The side metal thin film 116 is formed in a multi-sided structure, so that when the bottom surface 102 of the package body 110 is placed in the mounting area, the lower inclined surface 116c and the center surface 116a of the side metal thin film 116 are formed. Solder 150 is soldered. In this case, due to the inclined structure of the lower inclined surface 116c, the wettability of the solder 150 may be good, and heat dissipation efficiency between the solder pattern to be mounted and the side metal thin film 116 of the package body may be improved.

7 and 8 (a) (b) is a view showing a modification of the outer metal thin film according to the embodiment of the present invention, the metal thin film of any one side of the outer metal thin film may be partially formed on the side. .

As illustrated in (a) and (b) of FIG. 7, the front metal thin film 114a of the package body 110 may be formed at a portion of the front width W1 of the package body 110. For example, the front metal thin film 114a may be formed only in the width W3 of the front width W1 of the package body 110 except for the width W2 of the upper or lower center of the package body 110. The width W3 of the front metal thin film 114a may be narrower or wider than the width of the cavity 120. As shown in (a) and (b) of FIG. 8, the front metal thin film 114b of the package main body 110 is formed on the front side of the front side (that is, the side opposite to the mounting direction) except for the width W2 of the front side lower side. The front metal thin films 114a and 114b shown in FIGS. 7 and 8 may prevent the solder soldered to the side metal thin film 116 from spreading to the front surface of the package body.

9 is a view showing a light emitting diode package manufacturing process according to the present invention.

As shown in FIG. 9, cutting grooves 201 are formed in the package main body 200, which is one disc, at package long axis intervals, and package body arrays 202 are respectively disposed between the cutting grooves 201. Form Each package body is formed with a cavity, and then a metal blocking part is installed at a portion corresponding to the open area 222. Then, the plating or coating process is performed to plate or coat the entire front side, the entire side, and the rear part of the package body array to form a metal thin film. In this case, when the metal blocking part is removed, the metal thin film is not formed in the non-metal part line, and the metal thin film electrically separated from the left / right area of the package body may be formed by the open area 222.

The light emitting diode is mounted in the cavity and cut along the cutting line 205 in package units, thereby completing the light emitting diode package shown in FIG. 2.

An embodiment of the present invention is a side surface light emitting device using a light emitting diode package 100, one or more light emitting diode package and a light guide plate made of PMMA, PC material which is a light guide member in the light emitting direction of the light emitting diode. ) Can be irradiated with a surface light source. In addition, the reflective sheet may be provided under the light guide plate to reflect the leaked light again, and one or more optical sheets (eg, diffusion sheet, prism sheet, etc.) may be provided on the light guide plate.

The surface light emitting device of the present invention can be used as a light emitting device such as a light source such as a front light and / or a back light of a liquid crystal display device such as a portable terminal, or an illumination field.

Although the present invention has been described above with reference to the embodiments, these are merely examples and are not intended to limit the present invention. Those skilled in the art to which the present invention pertains should be provided within the scope not departing from the essential characteristics of the present invention. It will be appreciated that various modifications and applications are not possible.

For example, each component shown in detail in the embodiment of the present invention may be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

According to the light emitting diode package according to the present invention, a method of manufacturing the same, and a surface light emitting device, by forming a metal thin film on the inside / outside surface of the cavity of the package body, the reflection and electrode functions can be integrally provided.

In addition, the metal thin film inside the cavity can increase the light reflectance in the cavity, thereby improving the center luminance.

It is also possible to provide a path for heat dissipation to a thin metal film formed on the inner / outer surface of the cavity.

Claims (26)

A package body in which a cavity is formed; An inner metal thin film electrically open and formed inside the cavity; An outer metal thin film connected to the inner metal thin film and formed on an outer surface of the package body; A light emitting diode package comprising a light emitting diode mounted on an inner metal thin film of the cavity. The method of claim 1, The package body is a light emitting diode package using any one of a polymer material, a resin material, a ceramic material. The method of claim 1, The outer metal thin film may include a front metal thin film formed on the front surface of the package body in which the cavity is formed, and a side metal thin film connected to the front metal thin film and formed on left and right sides of the package body. The method of claim 3, wherein The front metal thin film is a light emitting diode package formed on the entire front surface or a portion of the front surface of the package body. The method of claim 3, wherein The front metal thin film formed on a portion of the front surface of the package body is formed in the front center or one side of the front center. The method of claim 1, The metal thin film is a light emitting diode package formed of 1um ~ 22um. The method of claim 1, The metal thin film is a light emitting diode package including a reflective layer using Ag or Al. The method of claim 1, The metal thin film is a light emitting diode package formed of one or more layers using a reflective material. The method of claim 7, wherein A light emitting diode package comprising an adhesive layer formed using at least one of Ni, Ti, Cr, and Cu between the surface of the package body and the reflective layer. The method of claim 1, The light emitting diode package of at least one of the AlGaN, GaN, InGaAlp, GaAs series LED chip. The method of claim 3, wherein The outer metal thin film is a light emitting diode package comprising a rear metal thin film is connected to the side metal thin film and extends to a portion of the rear surface of the package body. The method of claim 3, wherein The side metal thin film is formed on the side of the package body, the upper and lower inclined surface inclined at an angle to the upper and lower surfaces of the package body from the side surface. The method of claim 1, A light emitting diode package comprising a mold member molded in the cavity. The method of claim 13, A light emitting diode package comprising a phosphor contained in the mold member. The method of claim 1, The cavity is a light emitting diode package having an angle between the bottom surface and the circumferential surface of 90 ° ~ 120 ° range. The method of claim 1, The package body has a light emitting diode package having at least a polyhedron shape. Forming a cavity in the front of the package body; Forming an electrically open area in the cavity and in front of the package body; Forming a metal thin film on the inside of the cavity and on the front surface of the package body and on the left and right sides of the package body;  And mounting a light emitting diode inside the cavity having the electrically open area. The method of claim 17, The metal thin film is a method of manufacturing a light emitting diode package formed by any one of sputtering, vapor deposition, plating, coating method. The method of claim 17, The metal thin film is a light emitting diode package manufacturing method which is separated into two electrode regions by the electrically open region. The method of claim 17, The metal thin film is a light emitting diode package manufacturing method comprising a reflective layer using Ag or Al. The method of claim 17, The metal thin film comprises an adhesive layer using at least one of Ni, Ti, Cr, Cu, and a reflective layer using Ag or Al formed on the adhesive layer. The method of claim 17, The forming of the metal thin film may include forming a portion from the left / right side of the package body to a rear surface thereof. The method of claim 17, The metal thin film formed on the front surface of the package body is a light emitting diode package manufacturing method is formed in the central region or the central region of the front surface of the package body. The method of claim 17, The left / right side of the package body is a light emitting diode package manufacturing method having a multi-sided structure. The method of claim 17, When the light emitting diode is mounted, cutting the LED package by one or more cavity units. The light emitting diode package of claim 1; A surface light emitting device using the light emitting diode package as a light source.

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