TWI462348B - Light emitting device and fabrication method thereof - Google Patents

Description

Light-emitting device and its preparation method

The invention relates to a light-emitting device and a manufacturing method thereof, in particular to a light-emitting device with a small volume and a manufacturing method thereof.

With the advancement of the electronics industry and the advent of the digital era, various electronic products have gradually evolved toward the trend of functional integration, and can integrate various products into a single portable device to enhance the user's convenience and further break through the original. There are space limitations, so for example, how to integrate various types of light-emitting devices, such as light-emitting diodes (LEDs), on a computer into a small-sized portable device such as a mobile phone or a personal digital assistant (PDA). The device is undoubtedly the challenge of the next generation electronics industry.

Referring to FIG. 1A, a light-emitting device disclosed in US Pat. No. 7,732,234, comprising: a light-transmitting plate 10 having a first surface 10a and a second surface 10b opposite thereto, and a portion disposed on the light-transmitting plate 10 A solder ring 14 on the second surface 10b, a carrier 13 provided on the second surface 10b of the light-transmitting plate 10 by the solder ring 14, and a light-emitting element 12 provided on the carrier 13. The light transmissive plate 10 has a phosphor powder 100. The carrier member 13 has a recess 130 for receiving the light-emitting component 12, a line 132 disposed at the bottom of the recess 130, and a conductive via 131 electrically connected to the line 132 at one end. The sidewall surface of the recess 130 is formed The material is a metal mirror surface 130a, and the other end of the conductive via 131 is electrically connected to the solder ball 15 for external connection of other components. The light-emitting element 12 is a light-emitting diode to electrically connect the line 132 through the wire 11.

Referring to FIG. 1B, another conventional light-emitting device includes: a light-transmitting plate 10 having a first surface 10a and a second surface 10b opposite to each other, and a second surface 10b disposed on the second surface 10b of the light-transmitting plate 10. A piece 13', and a light-emitting element 12 provided on the carrier 13'. The light transmissive plate 10 has a phosphor powder 100. The carrier 13' has a heat dissipation plate 13b for carrying the light-emitting element 12, a lead frame 13a surrounding the light-emitting element 12, and an encapsulant 133 covering the heat dissipation plate 13b and the lead frame 13a. The bottom of the heat dissipation plate 13b is exposed. The encapsulant 133, and the lead leg 13a protrudes from the encapsulant 133, and the encapsulant 133 has a recess 130 to receive the illuminating element 12. The light-emitting element 12 is a light-emitting diode to electrically connect the lead pins of the lead frame 13a by wires 11.

However, in the conventional light-emitting device, the surface of the light-transmitting plate 10 is flat, so that the total internal reflection is easily generated around the light-transmitting plate 10, resulting in light extraction efficiency of the light-emitting element 12. low.

Moreover, in the conventional light-emitting device, the light-emitting element 12 is electrically connected to the line 132 on the carrier 13 or the lead-in leg of the lead frame 13a by the wire 11, so that a larger groove 130 space is required, so that the light-emitting device The overall package size of the device needs to be increased.

Therefore, how to provide a light-emitting device to overcome various shortcomings of the above-mentioned prior art is an important subject.

The invention provides a light-emitting device and a manufacturing method thereof, which can not only improve the light-emitting efficiency, but also reduce the overall package volume.

In order to achieve the above and other objects, the present invention provides a light emitting device comprising: a light transmissive plate having a first surface and a second surface; a conductive layer disposed on the second surface of the light transmissive plate; a carrier on the second surface of the light-transmitting plate and electrically connected to the conductive layer; and a light-emitting element disposed on the carrier and electrically connected to the conductive layer.

The invention provides a method for fabricating a light-emitting device, comprising: providing a light-transmitting plate having a first surface and a second surface; forming a conductive layer on a portion of the second surface of the light-transmitting plate; and providing the light-transmitting The second surface of the board is coupled to a carrier on which the light-emitting element is disposed, such that the conductive layer is electrically connected to the carrier and the light-emitting element.

In the above illuminating device and the manufacturing method thereof, the first surface of the light-transmitting plate is formed with a concave-convex structure, so that the total reflection of light is eliminated by the concave-convex structure, so that the concave-convex structure can be regular in the plane direction of the light-transmitting plate Distribution, but there are no special restrictions.

Furthermore, in the above light-emitting device and the method of manufacturing the same, the light-emitting element is electrically connected to the carrier by the conductive layer, so that the light-emitting element has an electrode pad electrically connected to the conductive layer, and the carrier can have electricity The conductive vias of the conductive layer are connected.

The light-emitting device of the present invention and the manufacturing method thereof have the concave-convex structure on the light-transmitting plate to avoid total reflection around the light-transmitting plate, thereby effectively achieving the purpose of improving light-emitting efficiency. Furthermore, the light-emitting element is electrically connected to the carrier by the conductive layer on the transparent plate, which not only reduces the groove space, but also reduces the overall package volume, and simplifies the process.

The other embodiments of the present invention will be readily understood by those skilled in the art from this disclosure.

The structure, the proportions, the sizes, and the like, which are illustrated in the specification of the present specification, are used for the purpose of understanding and reading by those skilled in the art, and are not intended to limit the present invention. The conditions that can be implemented are not technically meaningful, and any modification of the structure, change of the proportional relationship or adjustment of the size should be continued without affecting the effects and objectives of the present invention. It is within the scope of the technical contents disclosed in the present invention. In the meantime, the terms "upper", "one" and "two" are used in the description for convenience of description, and are not intended to limit the scope of the invention, and the relative relationship may be changed or Adjustments, where there is no material change, are considered to be within the scope of the invention.

Please refer to FIGS. 2A to 2D, which are schematic cross-sectional views showing the manufacturing method of the light-emitting device of the present invention.

As shown in FIG. 2A, a light-transmitting plate 20 having a first surface 20a and a second surface 20b opposite to each other is provided. The light-transmitting plate 20 is a glass plate, and the light-transmitting plate 20 has a phosphor powder (Phosphor). 200.

As shown in Figs. 2B and 2B', the first surface 20a of the light-transmitting sheet 20 is formed into the uneven structure 201, 201' by a concave-convex process such as chemical etching or physical polishing. In the embodiment, the concave-convex structures 201, 201' are regularly distributed in the plane direction of the light-transmitting plate 20, and the side view of the convex portion is, for example, curved (as shown in FIG. 2B') or V-shaped (eg, 2B)), but there are no special restrictions.

As shown in FIG. 2C, the conductive layer 21 is formed on a portion of the second surface 20b of the light-transmitting plate 20 by a patterned wiring process, and the material of the conductive layer 21 is made of a transparent material, for example, indium tin oxide. Indium Tin Oxide (ITO), or Antimony Tin Oxide (ATO). Among them, in the LCD industry, the indium tin oxide (ITO) is often used as a transparent conductive layer composed of 90% of indium plus 10% of tin.

As shown in FIG. 2D, a plurality of light-emitting elements 22 are provided. The light-emitting elements 22 are light-emitting diodes, and each of the light-emitting elements 22 has a plurality of electrode pads 220. A carrier member 23 is further provided. The carrier member 23 can be a package substrate having a recess 230 for receiving the light-emitting elements 22 in the recess 230.

Then, the second surface 20b of the transparent plate 20 (where the conductive layer 21 is not covered) is bonded to the carrier 23 by an adhesive layer 24, and the carrier 23 has a plurality of conductive vias 231. The conductive layer 21 is electrically connected, and the light-emitting element 22 is electrically connected to the conductive layer 21 by the electrode pads 220.

Furthermore, the recess 230 is formed by etching, and the side wall surface 230a thereof can serve as a reflecting surface. Moreover, one end of the conductive via 231 is electrically connected to the conductive layer 21, and the other end of the conductive via 231 is electrically connected to the solder ball 25 for connection to an electronic device (not shown) such as a circuit board. In addition, the material of the adhesive layer 24 may be, for example, a photo-curable resin (UV adhesive), a photoresist (PR), a dry film or a Benzocyclobutene (BCB).

Referring to Figure 2D', another embodiment of the carrier 23' of the present invention is shown. The difference between this embodiment and the above embodiment is only in the structure of the carrier 23'. The related structures of other illuminating devices are substantially the same, and therefore will not be described again.

The carrier member 23' has a heat dissipation plate 23b for carrying the light-emitting element 22, a lead frame 23a surrounding the light-emitting element 22, a second surface 20b disposed on the light-transmitting plate 20, and covering the heat dissipation plate 23b. The encapsulant 233 of the lead frame 23a and the conductive via 231 ′ are disposed on the encapsulant 233 and electrically connected to the conductive layer 21 .

The bottom of the heat dissipation plate 23b is exposed to the encapsulant 233, and the lead leg of the lead frame 23a protrudes from the encapsulant 233, and the encapsulant 233 forms the recess 230 to receive the light emitting element 22.

The present invention is characterized in that the concave-convex structure 201, 201' is formed on the first surface 20a of the light-transmitting plate 20 to eliminate total reflection of light, and the light-transmitting plate 20 of the present invention can be compared with the flat surface of the light-transmitting plate of the prior art. By avoiding total reflection around the light, the light extraction efficiency of the light-emitting element 22 can be improved, and good light controllability can be achieved.

In addition, the light-emitting element 22 of the present invention is electrically connected to the conductive via 231 of the carrier 23 by the conductive layer 21 on the second surface 20b of the transparent plate 20, compared to the conventional wire bonding method. The groove 230 of the present invention has a significantly smaller space, so that the light-emitting device of the present invention can greatly reduce the overall package volume.

Moreover, the present invention simplifies the process of fabricating the illuminating device by replacing the conventional wire bonding process with a conductive line deposition process.

The present invention provides a light-emitting device comprising: a light-transmitting plate 20 having a first surface 20a and a second surface 20b opposite thereto, and a conductive layer 21 disposed on a portion of the second surface 20b of the light-transmitting plate 20, The carrier member 23 of the second surface 20b of the transparent plate 20 is electrically connected to the conductive layer 21, and the light-emitting element 22 is disposed on the carrier 23 and electrically connected to the conductive layer 21.

The light-transmitting plate 20 is a glass plate and has a phosphor powder 200 dispersed therein, and the first surface 20a of the light-transmitting plate 20 is a concave-convex structure regularly distributed in the plane direction of the light-transmitting plate 20. 201, the side of the convex portion is regarded as an arc or a V shape. In addition, the second surface 20b of the light-transmitting plate 20 is bonded to the carrier 23 by an adhesive layer 24.

The carrier member 23 has a recess 230 for receiving the light-emitting element 22 and a conductive via 231 electrically connected to the conductive layer 21. The sidewall surface 230a of the recess 230 is a reflective surface.

The light-emitting element 22 is a light-emitting diode having an electrode pad 220 for electrically connecting the conductive layer 21.

In another aspect, the carrier member 23' has a heat dissipation plate 23b carrying the light-emitting element 22, a lead frame 23a surrounding the light-emitting element 22, and a second surface 20b disposed on the light-transmitting plate 20 and The encapsulant 233 covering the heat dissipation plate 23b and the lead frame 23a, and the conductive via 231' penetrating the encapsulant 233 and electrically connecting the conductive layer 21. The bottom of the heat dissipation plate 23b is exposed to the encapsulant 233, and the lead leg of the lead frame 23a protrudes from the encapsulant 233, and the encapsulant 233 forms the recess 230 to receive the light emitting element 22.

In summary, the light-emitting device of the present invention and the method for manufacturing the same are characterized in that the light-convex structure on the light-transmitting plate is used to avoid total reflection around the light-transmitting plate, thereby effectively improving the light-emitting efficiency.

Furthermore, the light-emitting element is electrically connected to the carrier by the conductive layer on the light-transmissive plate, which not only reduces the groove space, but also reduces the overall package volume, and simplifies the process.

The above embodiments are intended to illustrate the principles of the invention and its effects, and are not intended to limit the invention. Any of the above-described embodiments may be modified by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention should be as set forth in the appended claims.

10, 20. . . Idol

10a, 20a. . . First surface

10b, 20b. . . Second surface

100, 200. . . Fluorescent powder

11. . . wire

12, 22. . . Light-emitting element

13, 13', 23, 23’. . . Carrier

13a, 23a. . . Lead frame

13b, 23b‧‧‧ heat sink

130, 230‧‧‧ grooves

130a‧‧‧Mirror surface

131, 231, 231'‧‧‧ conductive through holes

132‧‧‧ lines

133, 233‧‧‧Package colloid

14‧‧‧ solder ring

15, 25‧‧‧ solder balls

201, 201'‧‧‧ concave and convex structure

21‧‧‧ Conductive layer

220‧‧‧electrode pad

230a‧‧‧ side wall

24‧‧‧Adhesive layer

1A and 1B are schematic cross-sectional views of light-emitting devices of different conventional aspects;

2A to 2D are schematic cross-sectional views showing a method of fabricating the light-emitting device of the present invention, wherein the 2B' diagram is another embodiment of the 2B diagram; and the 2D' diagram is another embodiment of the 2D diagram. .

20. . . Idol

20a. . . First surface

20b. . . Second surface

200. . . Fluorescent powder

201. . . Concave structure

twenty one. . . Conductive layer

twenty two. . . Light-emitting element

220. . . Electrode pad

twenty three. . . Carrier

230. . . Groove

230a. . . Side wall surface

231. . . Conductive through hole

twenty four. . . Adhesive layer

25. . . Solder ball

Claims (27)

A light-emitting device includes: a light-transmitting plate having a first surface and a second surface opposite to each other, the light-transmitting plate having a phosphor powder dispersed therein; and a conductive layer contacting the second layer of the light-transmitting plate On the surface, the carrier is disposed on the second surface of the light-transmitting plate and electrically connected to the conductive layer; and the light-emitting element is disposed on the carrier and electrically connected to the conductive layer to enable the light to be emitted The component is between the conductive layer and the carrier. The light-emitting device of claim 1, wherein the light-transmitting plate is a glass plate. The light-emitting device of claim 1, wherein the first surface of the light-transmitting plate is formed with a concave-convex structure. The light-emitting device of claim 3, wherein the uneven structure is regularly distributed in a planar direction of the light-transmitting plate. The illuminating device of claim 4, wherein the side of the convex portion of the uneven structure is regarded as an arc or a V shape. The illuminating device of claim 1, wherein the second surface of the light transmissive plate is bonded to the carrier by an adhesive layer. The light-emitting device of claim 1, wherein the carrier has a recess for receiving the light-emitting element and a conductive via for electrically connecting the conductive layer. The illuminating device of claim 7, wherein the side wall surface of the groove is a reflecting surface. The light-emitting device of claim 1, wherein the carrier has a lead frame surrounding the light-emitting element, an encapsulant disposed on the second surface of the light-transmitting plate and covering the lead frame, and a conductive via extending through the encapsulant and electrically connected to the conductive layer, wherein the encapsulant forms a recess to receive the light emitting component. The illuminating device of claim 9, wherein the carrier has a heat dissipating plate carrying the illuminating element, and the encapsulant covers the heat dissipating plate, and one side of the heat dissipating plate is exposed to the package colloid. The illuminating device of claim 9, wherein the lead leg of the lead frame protrudes from the encapsulant. The illuminating device of claim 1, wherein the illuminating element has an electrode pad electrically connected to the conductive layer. The illuminating device of claim 1, wherein the illuminating element is a light emitting diode. A method for fabricating a light-emitting device, comprising: providing a light-transmitting plate having a first surface and a second surface opposite to each other, wherein the light-transmitting plate has a phosphor powder dispersed therein; and contacting the conductive layer to form a second layer of the light-transmitting plate And affixing the second surface of the light-transmitting plate to a carrier member on which the light-emitting element is disposed, such that the light-emitting element is located between the conductive layer and the carrier member, so that the conductive layer is electrically connected The carrier and the light emitting element. The method of fabricating a light-emitting device according to claim 14, wherein the light-transmitting plate is a glass plate. The method of fabricating a light-emitting device according to claim 14, wherein the first surface of the light-transmitting plate forms a concave-convex structure. The method of fabricating a light-emitting device according to claim 16, wherein the uneven structure is formed by an etching process or a polishing process. The method of fabricating a light-emitting device according to claim 16, wherein the uneven structure is regularly distributed in a planar direction of the light-transmitting plate. The method of manufacturing a light-emitting device according to claim 18, wherein the side of the convex portion of the uneven structure is regarded as an arc or a V shape. The method of fabricating a light-emitting device according to claim 14, wherein the second surface of the light-transmitting plate is bonded to the carrier by an adhesive layer. The method of fabricating a light-emitting device according to claim 14, wherein the carrier has a recess for receiving the light-emitting element and a conductive via for electrically connecting the conductive layer. The method of fabricating a light-emitting device according to claim 21, wherein the side wall surface of the groove is a reflecting surface. The method of manufacturing the illuminating device of claim 14, wherein the carrier has a lead frame around the illuminating element, an encapsulant disposed on the second surface of the transparent plate and covering the lead frame And a conductive via extending through the encapsulant and electrically connecting the conductive layer, wherein the encapsulant forms a recess to receive the light emitting component. The method of manufacturing the illuminating device of claim 23, wherein the carrier has a heat dissipating plate carrying the illuminating element, and the encapsulant covers the heat dissipating plate, and one side of the heat dissipating plate is exposed The package colloid. The method of fabricating a light-emitting device according to claim 23, wherein the lead leg of the lead frame protrudes from the encapsulant. The method of fabricating a light-emitting device according to claim 14, wherein the light-emitting element has an electrode pad electrically connected to the conductive layer. The method of fabricating a light-emitting device according to claim 14, wherein the light-emitting device is a light-emitting diode.