TWI472067B - Optical package and method of manufacturing the same - Google Patents

Description

Optical package and method of manufacturing same

The Korean Patent Application No. 10-2010-0039715, filed on Apr. 28, 2010, and the Korean Patent Application No. 10-2010-0042047, filed on May 4, 2010 Priority is claimed on Korean Patent Application No. 10-2010-0042045, filed on Jan. 4, 2010, the entire disclosure of which is hereby incorporated by reference.

The present invention relates to an optical package and a method of fabricating the same, and more particularly to an optical package and a method of fabricating the same, which can reduce package volume and thickness, increase integration, and improve luminance and photoefficiency.

A light-emitting diode (LED) refers to an intermetallic compound junction diode that injects a minority carrier (eg, an electron or a hole) using a semiconductor PN interface structure and changes electrical energy by recombination through a carrier. Light can emit light. That is, when a forward voltage is applied to a semiconductor of a specific element, electrons and holes are removed and then recombined via the junction of the positive and negative electrodes. When the electrons and holes are recombined, the energy is smaller than when the electrons and holes are separated from each other. Therefore, because of the difference in energy, the LED emits light. LEDs are used not only in general display devices, but also in backlight elements of light-emitting devices or LCDs, and the application of LEDs has become widespread. In particular, LEDs have the advantage of being able to be driven by relatively low voltages, resulting in lower heat due to high energy effects, and having a longer lifetime. Therefore, LEDs are expected to develop high-brightness white light technology that was difficult to achieve in the past, and replace most of the existing light source devices.

1 is a cross-sectional view of an LED package in accordance with an embodiment of the prior art. Referring to FIG. 1, the LED package is configured to illuminate a gallium nitride (GaN) compound wafer via a live wire of the wire 102 and to dissipate heat through the heat sink 10 below. Furthermore, by wire bonding through the metal wires, power can be supplied to the LED package to an external support and an LED package portion such that the configuration of the LED package emits light. The above structure forms a package of the wafer 60.

The above conventional LED package forms a lead frame type package type. However, this leadframe type is therefore difficult to integrate with LED chips because of the low available package area. Moreover, when the leadframe type is mounted on the product, the leadframe type will inevitably increase the outer area or thickness of the product because the wafer size makes the package size relatively large.

In addition, the conventional LED package requires a heat sink below to release heat generated from the LED chip, and thus the volume and thickness of the LED package will also increase.

2 is a cross-sectional view of an LED package in accordance with another embodiment of the prior art.

Referring to FIG. 2, in the process of bonding the protective wires 102, after the phosphor material and the resin composite are coated, a plastic lens 25 is used to linearize the light and improve the light efficiency. This causes a problem of the limitation of the above-mentioned LED package reduction and the cost of the process.

Therefore, there is a need for a low cost, smaller size, and simpler process to fabricate LED packages.

Accordingly, the present invention has been made in view of the above problems, and it is therefore an object of the present invention to provide an optical package and a method of fabricating the same that have reduced optical package volume, reduced thickness and external volume of the final product, and integrated integration. The ability to reduce and reduce size. Furthermore, another object of the present invention is to provide an optical package and a method of fabricating the same that can reduce light absorption by an insulating layer and increase brightness and light efficiency by plating a metal layer. The heat sink and the bracket, or a light reflecting layer is plated and a white reflective layer is formed on an upper surface or surface of the insulating layer, or a metal reflective layer and a plating layer are formed on the surface of the insulating layer.

To achieve the above object, according to an embodiment of the invention, an optical package includes a metal layer disposed with a line pattern, an insulating layer formed on the metal layer and provided with a plurality of holes, and a hole disposed therein An optical component, a plurality of connection units configured to electrically connect the optical component and the line pattern, and a resin unit for burying the optical component and the connection unit. Therefore, the optical package can be downsized and integrated using a tape type insulating film without using a lead.

In particular, the optical package further comprises a reflective layer formed on a portion or an integral surface of a surface of the insulating layer. Therefore, brightness and light efficiency can be increased by the reflective layer.

Furthermore, it is preferred that the reflective layer be a white reflective layer or a metal layer.

Furthermore, the optical package may further comprise a light reflecting layer or a plating layer formed on the metal layer exposed through the holes.

Further, it is preferable that the reflective layer has an inclined surface on the side of the insulating layer, so that light can be reflected upward.

Further, it is preferred that the white reflective layer bury the sides of the insulating layer to a thickness of from 10 micrometers to 100 micrometers.

Further, the white reflective layer can be formed by printing one of a silver paste, a white solder resist, and a white resin.

Further, it is preferable that the metal reflective layer contains at least one of silver (Ag), nickel (Ni), copper (Cu), platinum (Pt), palladium (Pd), and gold (Au).

Further, it is preferable that the light reflecting layer or the plating layer be formed on the other side of the metal layer having the insulating layer stacked thereon.

Further, the light reflecting layer may contain silver (Ag) or the plating layer may contain at least one of silver (Ag), nickel (Ni), copper (Cu), platinum (Pt), palladium (Pd), and gold (Au).

Further, it is preferable that the metal layer is a copper layer or the insulating layer is a polyimide film.

Further, the resin unit has a convex mirror shape and contains a fluorescent substance and a transparent resin.

Further, it is preferred that the transparent resin be made of bismuth (Si).

A method of fabricating an optical package according to an embodiment of the invention comprises the steps of: (a) forming a plurality of holes in an insulating layer; (b) pressing a metal layer under the insulating layer and in the metal layer Forming a line pattern; (c) mounting an optical unit in a hole in the holes and electrically connecting the optical element and the line pattern via a plurality of connecting units; and (d) forming to bury the optical a unit and a resin unit of the connecting units.

In particular, the optical package may further comprise the step (b') of forming a reflective layer on a portion or the entire surface of a surface of the insulating layer after the step (b).

Further, preferably, the step (b') comprises forming a white reflective layer or a metallic reflective layer.

Furthermore, the method may further comprise the step (b-1) of forming a light reflecting layer exposed to the metal layer through the via after the step (b).

Furthermore, the method may further comprise the step (b-2) of forming a plating layer exposed to the metal layer via the via after the step (b).

Furthermore, it is preferred that the step (b-1) further comprises forming a side of the light reflecting layer on which the insulating layer is stacked.

Further, preferably, the step (b-2) further comprises forming a plating layer on a side having the insulating layer stacked thereon.

According to the present invention, the entire volume and thickness of the package can be reduced in accordance with a package formed by using an existing lead frame of a tape substrate. Furthermore, a highly integrated package can be produced by forming a package of a surface emitting method in a dot-emitting method. In addition, the cost can be reduced, the process can be simplified, and productivity can be improved by simultaneously executing a package process and forming a lens-shaped program. Brightness and light efficiency can be improved via a plated light reflecting layer and a plated white reflective layer or a metal reflective layer and a plating layer formed on the surface of an insulating layer.

Hereinafter, embodiments of the invention will be described with reference to the drawings. However, the invention may be modified in various forms, and the embodiments are not intended to limit the invention. The embodiments of the present invention are intended to be illustrative, and thus, in order to illustrate, FIG.

3 is a cross-sectional view showing a comparison of an LED package according to an embodiment of the prior art with an optical package according to an embodiment of the present invention, and FIGS. 4 to 6 are cross-sectional views showing an optical package according to another embodiment of the present invention.

As shown in FIG. 3, in the package structure of the present invention, an insulating layer 110 including a plurality of cells is formed with a metal layer 120 having a wiring pattern thereon. The structure further includes an optical element 150 disposed in the holes, a plurality of connection units 160 configured to electrically connect the optical elements 150 and the line pattern, and a resin unit configured to bury the optical element 150 and the connection units 160 170. A white reflective layer 130 (e.g., a reflective layer) is formed on an upper surface of the insulating layer 110. Preferably, a light reflecting layer 140 is plated on the metal layer 120 exposed through the holes. Here, it is preferable that the insulating layer 110 is a polyimide film and the metal layer 120 is made of copper (Cu). In the present invention, the white reflective layer 130 is formed on the upper surface of the insulating layer 110. Preferably, the white reflective layer 130 is formed by printing one of a silver paste, a white solder resist, and a white epoxy.

Generally, polyammonium has a brown or yellow color. However, polybendamine causes a problem of low brightness because it absorbs light instead of reflecting light. Therefore, a non-green series solder resist white reflective layer 130 is formed on the upper surface of the insulating layer 110 for increasing the brightness. In order to further increase the brightness, the white reflective layer 130 may be formed not only on the surface (for example, the upper surface) of the insulating layer 110 but also on the plurality of sides of the insulating layer 110 as shown in FIG. 4 or 5. Preferably, the sides of the insulating layer 110 are buried at a thickness of from 10 micrometers to 100 micrometers. The white reflective layer 130 has an inclined surface on the side of the insulating layer 110, so that light generated from the optical element 150 can be better reflected upward as shown in FIG. However, the distance (such as X in Fig. 5) between the side of the insulating layer 110 and the bottom surface of the inclined surface of the white reflective layer is preferably from 10 μm to 100 μm. As described above, the light generated from the optical element 150 is reflected upward by the inclined surface of the white reflective layer 130, so that the light efficiency can be increased. The white reflective layer 130 acts as a reflective layer to increase light efficiency. Furthermore, after the resin unit 170 is successively formed, the white reflective layer 130 acts as a barrier rib and serves as a spacer boundary.

Furthermore, the light reflecting layer 140 may be plated from the metal layer 120 where the white reflective layer 130 is not formed onto the metal layer 120 exposed through the holes. As shown, preferably, the light reflecting layer 140 is plated to the other side of the metal layer 120 of the stacked insulating layer 110. Preferably, the plating of the light reflecting layer 140 is silver (Ag) or plating containing silver.

As described above, the gold reflective layer 140 containing silver is not formed by gold plating as gold bonding. Therefore, the brightness is improved, the thermal conductivity is further increased, and the heat dissipation effect according to the heat generated from the optical element is also increased. Succession, reflexibility can also be increased, light adsorption can be prevented, and light efficiency can be maximized. Therefore, in the present invention, it is preferable that an LED chip (for example, the optical element 150) is disposed on the light reflecting layer 140 and electrically connected to a plurality of gold wires (for example, connecting units) interposed between the wafer and the line pattern. Bonded), and a strip-type LED package pattern in which the LED wafer and the gold wires are buried using the resin unit 170 can be performed. Preferably, the resin unit 170 has a convex mirror shape and contains a fluorescent substance and a transparent resin, and the transparent resin is made of bismuth (Si). As described above, the present invention can realize an integrated optical package and reduce the size via the film-type insulating film 110, and does not use a wiring pattern layer 121 of a lower heat sink and a metal wire portion. Furthermore, the wiring pattern layer 121 is formed under the insulating layer 110, and the wiring pattern layer 121 serves not only as a wiring board but also as a heat sink. Furthermore, wire bonding has an effect in that the bonding strength is quite good because the RZ is different according to a surface roughness.

6 is a cross-sectional view of an optical package in accordance with another embodiment of the present invention. Referring to FIG. 6, in the package structure of the present invention, a metal layer 120 having a wiring pattern is formed under an insulating layer 110 having a plurality of holes. Further, a metal reflective layer 135 is formed on the surface of the insulating layer 110, and a plating layer 145 is formed on the metal reflective layer 135 and the metal layer 120 exposed through the via. Preferably, the insulating layer 110 is a polyimide film. At the same time, it is preferred that the metal layer 120 be a copper layer. Furthermore, in the present invention, as described above, the metal reflective layer 135 is formed on the surface of the insulating layer (for example) Such as top and side). Preferably, the metal reflective layer 135 is coated with a conductive paste such as silver (Ag), nickel (Ni), copper (Cu), palladium (Pd), platinum (Pt), gold (Au) or Carbon is printed. Most preferably, the metal reflective layer 135 is printed by coating silver paste from the conductive paste. Generally, polyimine has a brown or yellow color. However, polyimine has a problem of low brightness because it absorbs light instead of reflecting light. For this reason, the metal reflective layer 135 and the plating layer 145 are formed not only on the upper surface of the insulating layer 110 but also on the plurality of sides thereof. Thus, the adsorption of light by the insulating layer 110 is reduced, and the light efficiency is increased. Preferably, the metal reflective layer 135 is formed, so that the insulating layer 110 is buried at a right angle to form a barrier wall shape, but therefore the barrier walls have an angle (i.e., a tilt) on a plurality of sides of the insulating layer 110. Face), as shown in Figure 6. Therefore, light generated from an optical element 150 is reflected upward by the inclined surface of the metal reflective layer 135, and thus has an ability to increase light efficiency. Further, the plating layer 145 as described above may be formed on the metal reflective layer 135 and the metal layer 120 exposed through the holes. Preferably, as shown in FIG. 6, a plating layer 145 is plated on one side of the metal layer 120 having the insulating layer 110 stacked thereon. Preferably, the plating layer 145 is formed of at least one of silver (Ag), nickel (Ni), copper (Cu), palladium (Pd), platinum (Pt), and gold (Au). As described above, gold plating is not used as wire bonding but is formed of silver (Ag), nickel (Ni), copper (Cu), palladium (Pd), platinum (Pt), or Gold (Au) plating layer 145. Therefore, the brightness is improved, the thermal conductivity is further increased, and the heat dissipation effect according to the heat generated from the LED wafer is also increased. As a result, the reflectance is increased and the absorption of light is avoided. Free and maximize light efficiency.

The optical element 150, the plurality of connection units 160, and a resin unit 170 in Fig. 6 are the same as those in Fig. 3, and thus the description thereof will be omitted.

7 is a top plan view of an optically encapsulated polyimide surface and line pattern unit in accordance with an embodiment of the present invention. As shown in FIG. 7, the optical package of the present invention is superior to the top view of the conventional LED package in terms of integration (refer to the figure on the right side of FIG. 3).

8 and 9 are cross-sectional views showing a manufacturing process of an optical package in accordance with another embodiment of the present invention. Referring to Figures 8 and 9, first, the channels 115 and 116 are formed in the insulating layer 110 via punching S2, P2. Preferably, the insulating layer 110 is a polyimide film. The channels 115 and 116 include a device hole 115 (e.g., a central hole where the optical component will be placed) and a plurality of via holes 116 through which wires (e.g., connection unit 160) are connected to provide power to Optical element.

Subsequently, the metal layer 120 is pressed into S3, P3. Preferably the metal layer is made of copper. Next, a surface is activated by a number of chemical treatments, a photoresist is applied to the surface, and an exposure and development process is performed. After the development process is completed, the desired wiring is formed through the etching process and the photoresist is removed, thereby forming the wiring pattern layer 121. Thereafter, a white reflective layer 130 is formed on the insulating layer 110 except for the surface for bonding and the via for providing an external power source.

In general, polyimine is electrically stable, but the problem is that it has poor reflectivity because its brown or yellow series of colors causes low light efficiency. Light efficiency can be borrowed It is increased by adding color from the white reflective layer 130. Preferably, the white reflective layer 130 is printed by one of a silver paste, a white solder mask, and a non-general green series solder resist white epoxy.

Preferably, the white reflective layer 130 is formed not only on the top surface of the insulating layer 110 but also on a plurality of sides of the insulating layer 110 as shown in FIG. 9 to improve brightness and light efficiency P4. When the white reflective layer 130 buryes a plurality of sides of the insulating layer 110 at a thickness of 10 micrometers to 100 micrometers, brightness and light efficiency can be most effectively increased. In particular, although the insulating layer 110 can be buried in a shape of a barrier wall at a right angle as shown in FIG. 4, it is preferable that the inclined surface is formed on the side of the insulating layer 110, so that light generated from the optical element can be as Figure 9 shows the upward reflection. Preferably, a distance between a side of the insulating layer 110 and a bottom surface of the inclined surface of the white reflective layer 130 (e.g., X in Fig. 9) is from 10 micrometers to 100 micrometers.

Next, through the surface treatment, the light reflecting layer 140 can be formed by plating the metal layer 120 exposed through the holes 115 and 116, and thus the metal layer 120 can be bonded to S5, P5. Here, it is preferable that the light reflecting layer 140 is also plated on a wiring surface (for example, the side of the metal layer 120 on which the insulating layer 110 is stacked) as shown. Further, it is preferable that the plating of the light reflecting layer 140 is plating with silver or silver. Since the above is not performed by gold plating but silver plating, light absorbed by the insulating layer 110 is reduced, and light efficiency is increased.

Next, via the die bonding, the optical element 150 is disposed at the optical element 150 of the light reflecting layer 140 formed in the via hole of the insulating layer 110 at the places S6, P6. It is best to use an adhesive to place the optics 150 (eg LED chip). Next, a plurality of gold wires are bonded to the silver-plated light-reflecting layer 140, thereby electrically connecting the wiring pattern layer 121 and the LED wafers 150 S7, P7. Next, the resin unit 170 is formed to embed the LED wafer 150 and the gold wires S8, P8. More specifically, a lens type resin unit completes optical packaging by excessively coating a phosphor material for a white LED and a transparent resin at a boundary portion of a white solder resist. In the case where the fluorescent substance and the transparent resin are excessively coated, the lens type resin unit 170 is formed due to the surface tension as shown. Therefore, the encapsulation process and the process of forming a plastic lens can be performed simultaneously.

Figure 10 is a cross-sectional view showing a manufacturing process of an optical package in accordance with another embodiment of the present invention. Steps Q1 to Q3 and Q6 to Q8 of Fig. 10 are similar steps to steps S1(P1) to S3(P3) and S6(P6) to S8(P8), so only the differences of Q4 and Q5 are mainly described. First, holes 115 and 116 are formed on the insulating layer 110 by stamping Q2. The metal layer 120 is pressed to form the wiring pattern layer 121 Q3.

Next, a metal reflective layer 135 (eg, a reflective layer) is formed over portion Q4 of the entire insulating layer 110. Preferably, the metal reflective layer 135 is printed by coating a conductive paste such as silver, nickel, copper, palladium, platinum, gold or carbon. Preferably, the metallic reflective layer 135 is printed by coating silver paste. Although the insulating layer 110 may be buried at right angles to form a barrier wall, it is preferable that the side edges of the insulating layer 110 form an inclined surface, so that light generated from the optical element 150 is reflected upward, as shown in FIG. Next, a plating layer 145 is formed on the metal reflective layer 135 and the metal layer 120 exposed through the vias 115 and 116, and is surface-bonded to bond Q5. Here, it is preferable that the plating layer 145 is also formed on a line. A face (for example, one side of the metal layer 120 having the insulating layer 110 stacked thereon) is as shown in FIG. Further, it is preferable that the plating layer 145 is made of silver, nickel, copper, palladium, platinum, or gold. In general, polyimine is electrically stable, but the problem is that it has poor reflectivity because its brown or yellow series of colors causes low light efficiency. Therefore, if the silver paste is coated as in the present invention, the polyimine region will disappear, the brillance will increase via the plating layer 145 as described above, and the light effect can be further increased. The steps following step Q6 are similar to those of Figs. 8 and 9 as described above, and thus the description will be omitted.

Figure 11 is a cross-sectional and top plan view showing the degree of integration of a detailed optical package in accordance with the teachings of the present invention. From Fig. 11, it can be clearly seen that if the LED package is formed in the same area, the present invention can be formed as compared with the LED wafer in which the metal lead 20 and the lower heat sink 10 are disposed (refer to the illustration on the left side of Figs. 3 and 11). There is a larger number of LED packages (refer to the illustration on the right side of Figure 11).

The preferred embodiment has been disclosed by way of illustration and description. Although a specific name is used, it is only used to describe the invention and should not be used to limit the meaning and scope of the claims of the invention. Thus, it will be apparent to those skilled in the <RTIgt; Therefore, the true technical scope of the present invention should be defined by the appended claims.

10‧‧‧heating device

20‧‧‧Metal lead

25‧‧‧Plastic lens

60‧‧‧ wafer

102‧‧‧ wire

110‧‧‧Insulation

115, 116‧‧ ‧ tunnel

120‧‧‧metal layer

121‧‧‧Line pattern layer

130‧‧‧White reflective layer

135‧‧‧Metal reflector

140‧‧‧Light reflection layer

145‧‧‧Electroplating

150‧‧‧Optical components

160‧‧‧ Connection unit

170‧‧‧Resin unit

X‧‧‧ distance

S1~S8‧‧‧Steps

P1~P8‧‧‧ steps

Q1~Q8‧‧‧Steps

1 is a cross-sectional view of an LED package in accordance with an embodiment of the prior art; FIG. 2 is a cross-sectional view of an LED package in accordance with another embodiment of the prior art; 3 is a cross-sectional view showing a comparison of an LED package according to an embodiment of the prior art with an optical package according to an embodiment of the present invention; and FIGS. 4 to 6 are cross-sectional views showing an optical package according to another embodiment of the present invention; FIG. 8 is a cross-sectional view showing a manufacturing process of an optical package according to an embodiment of the present invention; FIG. 9 is a cross-sectional view showing a manufacturing process of an optical package according to an embodiment of the present invention; FIG. A cross-sectional view of a manufacturing process of an optical package according to another embodiment of the present invention; and FIG. 11 is a cross-sectional view and a plan view showing the degree of integration of a detailed optical package according to the present invention.

110. . . Insulation

120. . . Metal layer

130. . . White reflective layer

140. . . Light reflection layer

150. . . Optical element

160. . . Connection unit

170. . . Resin unit

Claims (17)

An optical package comprising a metal layer formed with a line pattern; an insulating layer formed on the metal layer and configured with a plurality of holes; an optical component disposed in one of the holes; and a plurality of connecting units configured to electrically connect the wire An optical element and the wiring pattern; a reflective layer formed on at least one side of the insulating layer; a plating layer formed on the metal layer exposed through the holes and on the reflective layer; and a resin unit configuration The optical component and the connecting units are buried. The optical package of claim 1, wherein the reflective layer is further formed on an upper surface of the insulating layer. The optical package of claim 2, wherein the reflective layer is a white reflective layer or a metal reflective layer. The optical package of claim 2, wherein the reflective layer has an inclined surface on a side of the insulating layer such that light is reflected upward. The optical package of claim 3, wherein the white reflective layer buryes a side of the insulating layer at a thickness of from 10 micrometers to 100 micrometers. The optical package of claim 3, wherein the white reflective layer is formed by one of printing silver paste, white solder resist, and white resin. The optical package of claim 3, wherein the metal reflective layer comprises at least one of silver, nickel, copper, platinum, palladium, and gold. The optical package of claim 1, wherein the plating layer is formed on the other side of the metal layer having the insulating layer stack. The optical package of claim 8, wherein the plating layer comprises at least one of silver, nickel, copper, platinum, palladium, and gold. The optical package of claim 1, wherein the metal layer is a copper layer or the insulating layer is a polyimide film. The optical package of claim 1, wherein the resin unit has a convex mirror shape and comprises a fluorescent material and a transparent resin. The optical package of claim 11, wherein the transparent resin is made of tantalum. An optical package manufacturing method comprising the steps of: (a) forming a plurality of cells in an insulating layer; (b) pressing a metal layer under the insulating layer; and (c) forming a reflective layer on at least one of the insulating layers (d) forming a plating layer on the metal layer exposed through the holes and on the reflective layer; (e) placing an optical element in one of the holes and through the plurality of holes The connecting unit electrically connects the optical element to the metal layer; and (f) forms a resin unit for embedding the optical element and the connecting unit. The optical package manufacturing method of claim 13, further comprising the step (c) of forming the reflective layer on an upper surface of the insulating layer. The optical package manufacturing method of claim 14, wherein the step (c) comprises forming a white reflective layer or a metal reflective layer. The optical package manufacturing method of claim 13, wherein the step (c) further comprises forming a light reflecting layer on the other side of the metal layer having the insulating layer stack. The optical package manufacturing method of claim 13, wherein the step (c) further comprises forming a plating layer on the other side of the metal layer having the insulating layer stack.