TWI425673B - Light emitting diode package structure and method of manufacturing the same - Google Patents

Description

Light-emitting diode package structure and manufacturing method thereof

The present invention relates to a semiconductor light emitting device, and more particularly to a package structure of a light emitting diode and a method of fabricating the same.

The semiconductor light-emitting diode has been widely used in various fields, such as indicator lights, illumination lamps, display screens, etc., due to its high luminous efficiency, small size, light weight, and environmental protection.

Before applying the light-emitting diode to the above various fields, it is necessary to package the light-emitting diode wafer to protect the light-emitting diode wafer, thereby obtaining high luminous efficiency and long service life. A common LED package structure includes a substrate and a light emitting diode chip disposed on the substrate. The LED chip is electrically connected to the circuit structure on the substrate through a gold wire, and an encapsulation layer is formed on the substrate and coated. A light-emitting diode chip and a gold wire are used to protect the light-emitting diode chip. Generally, the industry uses stamper technology to form the encapsulation layer. However, during the molding process, the LED chip and the gold wire are easily damaged, which not only weakens the reliability of the connection between the LED and the external electrical connection, but also affects the illumination. The luminescent properties of the polar body wafer may cause the illuminating diode to malfunction normally.

In view of the above, it is necessary to provide a light emitting diode package structure and a manufacturing method thereof, in which the light emitting diode chip and the gold wire in the light emitting diode package structure are not damaged.

A light emitting diode package structure comprising:

a substrate having a first surface and a second surface opposite to the first surface, and at least two through holes penetrating the first surface and the second surface, the first surface having an electrical circuit structure;

a light emitting diode chip disposed on the first surface of the substrate and having solder joints on the light emitting diode wafer;

The mask layer is disposed on the first surface of the substrate and is disposed on the LED substrate, and the mask layer is provided with an opening corresponding to the solder joint on the LED substrate;

a gold wire, passing through the opening of the mask layer and electrically connecting the solder joint of the LED chip and the circuit structure of the substrate;

a phosphor layer filled between the mask layer and the first surface of the substrate, covering the LED chip and isolated from the gold wire, and sealing the through hole of the substrate;

The protective layer is disposed on the first surface of the substrate and covers the mask layer and the gold wire.

A manufacturing method of a light emitting diode package structure, the steps comprising:

Providing a substrate having a first surface and a second surface opposite to the first surface, and at least two through holes penetrating the first surface and the second surface, the first surface having an electrical circuit structure;

Fixing a light emitting diode chip on a first surface of the substrate, the light emitting diode chip having solder joints thereon;

The mask layer is disposed on the first surface of the substrate and is disposed on the LED substrate, and the mask layer is provided with an opening corresponding to the solder joint on the LED chip;

Passing the gold wire through the opening of the mask layer and electrically connecting the gold wire to the solder joint of the LED chip and the circuit structure of the substrate;

Fluorescent material is filled between the mask layer and the first surface of the substrate through the through hole of the substrate, and the phosphor material covers the light emitting diode wafer to form a fluorescent layer, and the fluorescent layer is isolated from the gold wire;

A protective layer is disposed on the first surface of the substrate and the mask layer and the gold wire cover are disposed in the protective layer.

The illuminating diode package structure of the present invention provides a mask layer covering the illuminating diode chip. By controlling the specification of the mask layer, the luminescent layer can only cover the illuminating diode chip, and the conventional stamper is discarded. The method is such that the phosphor layer does not cause any damage to the LED chip and the gold wire, thereby improving the yield of the LED package structure.

Referring to FIG. 10, a light emitting diode package structure according to an embodiment of the present invention includes a substrate 10, a light emitting diode chip 20 disposed on the substrate 10, and a mask layer 30 covering the light emitting diode chip 20. The gold wire 40 connecting the light-emitting diode chip 20 and the substrate 10 covers the fluorescent layer 50 of the light-emitting diode wafer 20 and the protective layer 60 covering the gold wire 40 and the mask layer 30.

The substrate 10 has a first surface 101 and a second surface 102 opposite the first surface 101. At least two through holes 12 penetrating the first surface 101 and the second surface 102 are also formed on the substrate 10. The through holes 12 are formed to form the phosphor layer 50. Therefore, the number and shape of the through holes 12 can be changed according to actual needs. For example, the number can be plural, and the shape can be circular, square, or the like. The distribution form of the through holes 12 is also not particularly limited, and may be distributed in the form of an array or a circle or the like around the light emitting diode wafer 20. Also provided on the first surface 101 is a circuit structure 14, which may include at least two electrodes 141.

The light emitting diode chip 20 is disposed on the first surface 101 of the substrate 10. The light-emitting diode wafer 20 has two solder joints 201 of opposite polarities. A solder pad may be added outside the solder joint 201 to increase the thickness of the solder joint to facilitate electrical connection between the gold wire 40 and the solder joint 201. The solder joints 201 of the light-emitting diode wafer 20 in this embodiment are all located above, so-called "same-sided electrodes". In other embodiments, the LED array 20 can be a vertical LED, and the solder joints 201 are respectively located above and below the LED array 20.

Referring to FIG. 3 simultaneously, the mask layer 30 is disposed on the first surface 101 of the substrate 10 and is disposed on the LED substrate 20, and a mask layer 30 is formed between the mask layer 30 and the first surface 101 of the substrate 10. The space 501 of the fluorescent layer 50 is accommodated. The mask layer 30 is made of a light transmissive material, so that light emitted from the LED chip 20 can be emitted to the outside through the mask layer 30. The mask layer 30 is provided with two openings 301 corresponding to the solder joints 201 on the LED array 20. If the LED array 20 is of a vertical type, only one opening 301 may be provided on the mask layer 30, that is, the number of the openings 301 coincides with the number of solder joints 201 above the LED array 20. When the phosphor layer 50 is formed, in order to prevent the liquid fluorescent material from oozing out of the mask layer 30, the size of the two openings 301 of the mask layer can be strictly controlled, so that the solder joint 201 of the LED wafer 20 is just exposed. At the opening 301, other portions are covered by the mask layer 30.

The gold wire 40 passes through the opening 301 of the mask layer 30 and electrically connects the pad 201 of the LED wafer 20 and the circuit structure 14 of the substrate 10. One end of each gold wire 40 is connected to the solder joint 201, and the other end is connected to the electrode 141 of the circuit structure 14. In different embodiments, different numbers of gold wires 40 may be disposed to connect the solder joint 201 and the electrode 141, for example three or more, but at least two, respectively connected to the opposite polarity of the LED body 20 Solder joint 201. If the LED chip 20 is of a vertical type, there may be only one gold wire 40 connected to the solder joint 201 located above the LED chip 20, and the solder joint 201 under the LED chip 20 may be It is in direct contact with the circuit structure 14 disposed on the substrate 10.

In an embodiment, a sealing layer 70 may also be disposed on the upper surface of the mask layer 30, and the sealing layer 70 may increase the bonding strength between the gold wire 40 and the solder joint 201. In addition, the sealant layer 70 can also seal the opening 301 of the mask layer 30 to prevent the liquid phosphor material from oozing out of the mask layer 30 from the opening 301 when the phosphor layer 50 is formed. In addition, a plurality of sealant layers 70 separated from each other may be disposed on the upper surface of the mask layer 30. As shown in FIG. 6, the two sealant layers 70 are isolated from each other and disposed only at the opening 301 of the mask layer 30. The glue amount and thickness of the sealant layer 70 are conveniently controlled. The phosphor layer may be contained in the sealant layer 70, and the sealant layer 70 may be made of a material such as tantalum resin, epoxy resin or a mixture of the two.

The phosphor layer 50 is filled in the space 501 between the mask layer 30 and the first surface 101 of the substrate 10, and covers the light emitting diode wafer 20 while sealing the through holes 12 of the substrate 10. The phosphor layer 50 contains phosphor powder, and the light emitted by the LED chip 20 passes through the phosphor layer 50, and emits light of a wavelength different from the original light, and is mixed with the original light to form a plurality of colors of light. For example, white light, etc.

The protective layer 60 is disposed on the first surface 101 of the substrate 10 and covers the mask layer 30 and the gold wire 40. The protective layer 60 is also made of a light transmissive material such that light that passes through the mask layer 30 can continue to pass through the protective layer 60 to the outside. The protective layer 60 may contain an inorganic material such as cerium oxide (SiO2), titanium oxide (TiO2), or the like.

The light-emitting diode package structure of the present invention is provided with the mask layer 30 so that the phosphor layer 50 is only wrapped around the light-emitting diode wafer 20 without any influence on the gold wire 40. At the same time, by controlling the mask layer 30, the thickness of the phosphor layer 50 can also be controlled, and the phosphor layer 50 can be uniformly covered on the LED chip 20, so that the forward light mixing energy of the LED can be further improved. Evenly.

Referring to FIG. 11 again, the circuit structure 14 in the LED package structure of the embodiment of the present invention may further include an extension layer 142 connecting the electrode 141 and extending from the first surface 101 of the substrate 10 to the first The two surfaces 102 are used to enlarge the area of the circuit structure 14 of the LED package structure, which facilitates subsequent installation and use of the LED package structure.

Referring to FIG. 12 again, the extension layer 142 can define a hole 143 corresponding to the through hole 12 in the substrate 10. After the phosphor layer 50 is formed, the hole 143 is sealed with the solder 80.

Referring to FIG. 13 again, a light emitting diode package structure according to an embodiment of the present invention may further form another sealing layer 90 on the second surface 102 of the substrate 10, and the other sealing layer 90 covers the through hole of the substrate 10. 12, used to protect the fluorescent layer 50 from damage.

Referring to FIG. 9 again, the LED package structure in the embodiment of the present invention can replace the fluorescent material in the through hole 12 of the substrate 10 to fill other functions such as the heat conductive material 15 after forming the phosphor layer 50. Sexual substance. The heat conductive material 15 may be a metal, a ceramic, a polymer material or a composite material thereof having high thermal conductivity. This not only increases the thermal conductivity of the substrate 10, but also protects the phosphor layer 50 from damage.

The structural features in the different embodiments described above can be reasonably transformed and combined. For example, the thermally conductive substance 15 in the through hole 12 of the substrate 10 may be covered by another sealant layer 90 formed on the second surface 102 of the substrate 10, or may be formed on the circuit structure 14 of the second surface 102 of the substrate 10. The extension layer 142 is covered. Another glue layer 90 may also partially replace the extension layer 142, coexisting with the extension layer 142.

The manufacturing method of the light emitting diode package structure of the present invention will be described below with reference to other drawings.

Referring to FIGS. 1 and 2, a substrate 10 is provided having a first surface 101 and a second surface 102 relative to the first surface 101. At least two through holes 12 penetrating the first surface and the second surface are formed on the substrate 10. The first surface 101 is provided with a circuit structure 14 comprising at least two electrodes 141. Further, a light-emitting diode wafer 20 is provided, and the light-emitting diode wafer 20 is placed on the first surface 101 of the substrate 10. The light-emitting diode wafer 20 has two solder joints 201 of opposite polarities. Of course, after the LED body 20 is fixed on the substrate 10, the substrate 10 is processed to form the through hole 12.

Referring to FIG. 3, the mask layer 30 is disposed on the first surface 101 of the substrate 10 and overlaid on the LED wafer 20. The through hole 12 of the substrate 10 is covered by the mask layer 30. A space 501 for accommodating the phosphor layer 50 is formed between the mask layer 30 and the first surface 101 of the substrate 10. The mask layer 30 is made of a light transmissive material, and light emitted from the LED chip 20 can be emitted to the outside through the mask layer 30. The mask layer 30 is provided with two openings 301 corresponding to the solder joints 201 on the LED array 20. The size of the two openings 301 of the mask layer 30 is strictly controlled such that the solder joint 201 of the LED wafer 20 is just exposed at the opening 301 and other portions of the LED wafer 20 are covered by the mask layer 30. Thereby, when the phosphor layer 50 is formed, the liquid fluorescent material can be prevented from oozing out of the mask layer 30.

Referring next to FIG. 4, the gold wire 40 is passed through the opening 301 of the mask layer 30 and electrically connected to the pad 201 of the LED wafer 20 and the circuit structure 14 of the substrate 10. One end of each gold wire 40 is connected to the solder joint 201, and the other end is connected to the electrode 141 of the circuit structure 14.

As shown in FIG. 5, in an embodiment, a sealing layer 70 is disposed on the upper surface of the mask layer 30, and the sealing layer 70 can increase the bonding strength between the gold wire 40 and the solder joint 201. In addition, the sealant layer 70 can also seal the opening 301 of the mask layer 30 to prevent the liquid phosphor material from oozing out of the mask layer 30 from the opening 301 when the phosphor layer 50 is formed. As shown in FIG. 6, the sealant layer 70 can also be disposed as two isolated from each other and disposed only at the opening 301 of the mask layer 30.

Referring to FIG. 7, the liquid fluorescent material 51 is injected into the space 501 between the mask layer 30 and the first surface 101 of the substrate 10 from a through hole 12 of the substrate 10. The air in the space 501 may be passed through another through hole. 12 discharge, as indicated by the arrow in FIG. The liquid fluorescent material 51 is coated around the light-emitting diode wafer 20 to form a fluorescent layer 50 after curing. Referring to FIG. 8, when the liquid fluorescent material 51 is injected, the substrate 10 can be inverted, so that the amount of the liquid fluorescent material 51 can be better controlled so as to be just filled around the LED wafer 20, and the substrate 10 is The through hole 12 is not filled with the liquid fluorescent material 51.

Referring to FIG. 9, in an embodiment, other functional substances such as the heat conductive material 15 may be filled in the through holes 12 not filled with the liquid fluorescent material 51. The heat conductive material 15 may be a metal, a ceramic, a polymer material or a composite material thereof having high thermal conductivity. Of course, in the light emitting diode package structure shown in FIG. 7, the liquid fluorescent material 51 in the through hole 12 of the substrate 10 can also be removed, and then the heat conductive material 15 can be filled in the through hole 12.

Referring to FIG. 10 again, a protective layer 60 is provided. The protective layer 60 is disposed on the first surface 101 of the substrate 10 and covers the mask layer 30 and the gold wire 40. The protective layer 60 is also made of a light transmissive material and may contain an inorganic material such as cerium oxide (SiO2), titanium oxide (TiO2) or the like.

Because the manufacturing method of the LED package structure provided by the present invention discards the conventional compression molding method, the phosphor layer 50 is only wrapped around the LED array 20 and is isolated from the gold wire 40 to make the LED. The bulk wafer 20 and the gold wire 40 are not damaged during the manufacturing process, and the production yield of the light emitting diode package structure can be ensured.

Referring to FIG. 11 again, after the phosphor layer 50 is formed, the electrode 141 of the circuit structure 14 may be extended to form the extension layer 142 of the second surface 102 of the substrate 10. The extension layer 142 of the circuit structure 14 covers the through hole 12 of the substrate 10, and the effect of expanding the area of the circuit structure 14 and protecting the fluorescent layer 50 can be achieved at the same time. Referring to FIG. 12 again, the extension layer 142 may be formed while forming the circuit structure 14 (before forming the phosphor layer 50), and corresponding holes 143 are reserved at the through holes 12 of the corresponding substrate 10 to be formed into a fluorescent layer. After the layer 50, the holes 143 are sealed with solder 80.

Referring to FIG. 13 again, instead of the partial extension layer 142 described above, another sealant layer 90 is formed on the second surface 102 of the substrate 10, and the other sealant layer 90 covers the through hole 12 of the substrate 10 for The fluorescent layer 50 is protected from damage. The other sealant layer 90 can be made of a material such as tantalum resin, epoxy resin, or a mixture of the two.

In addition, when the LED array 20 is of a vertical type, only one opening 301 is formed on the mask layer 30 corresponding to the solder joint 201 above the LED chip 20, and the solder joint 201 above the LED wafer 20 is transmitted through the gold. The wire 40 is connected to an electrode 141, and the solder joint 201 under the LED chip 20 can be directly connected to an electrode 141 on the substrate 10. The other steps are similar to those in the above embodiment, and therefore will not be described again.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

10‧‧‧Substrate

101‧‧‧ first surface

102‧‧‧ second surface

12‧‧‧through hole

14‧‧‧Circuit structure

141‧‧‧electrode

142‧‧‧Extension layer

143‧‧‧ hole

15‧‧‧ Thermal Conductive Materials

20‧‧‧Light Diode Wafer

201‧‧‧ solder joints

30‧‧‧mask layer

301‧‧‧ openings

40‧‧‧ Gold wire

50‧‧‧Fluorescent layer

501‧‧‧ space

51‧‧‧Liquid fluorescent materials

60‧‧‧Protective layer

70‧‧‧ Sealing layer

80‧‧‧ solder

90‧‧‧Another layer of glue

1 to FIG. 10 are schematic cross-sectional views showing a light emitting diode package structure obtained in each step of a method for fabricating a light emitting diode package structure according to the present invention.

11 to 13 are schematic cross-sectional views showing a light emitting diode package structure in different embodiments of the present invention.

10‧‧‧Substrate

101‧‧‧ first surface

102‧‧‧ second surface

12‧‧‧through hole

14‧‧‧Circuit structure

141‧‧‧electrode

20‧‧‧Light Diode Wafer

201‧‧‧ solder joints

30‧‧‧mask layer

40‧‧‧ Gold wire

50‧‧‧Fluorescent layer

501‧‧‧ space

60‧‧‧Protective layer

70‧‧‧ Sealing layer

Claims (10)

A light emitting diode package structure comprising:
a substrate having a first surface and a second surface opposite to the first surface, and at least two through holes penetrating the first surface and the second surface, the first surface having an electrical circuit structure;
a light emitting diode chip disposed on the first surface of the substrate and having solder joints on the light emitting diode wafer;
The mask layer is disposed on the first surface of the substrate and is disposed on the LED substrate, and the mask layer is provided with an opening corresponding to the solder joint on the LED substrate;
a gold wire, passing through the opening of the mask layer and electrically connecting the solder joint of the LED chip and the circuit structure of the substrate;
a phosphor layer filled between the mask layer and the first surface of the substrate, covering the LED chip and isolated from the gold wire, and sealing the through hole of the substrate; and a protective layer disposed on the first surface of the substrate Covered with a mask layer and gold wire. The light emitting diode package structure of claim 1, further comprising a sealant layer disposed at the opening of the mask layer and fixing the gold wire and the solder joint. The light emitting diode package structure according to claim 2, wherein another sealing layer is formed on the second surface of the substrate corresponding to at least two through holes. The light emitting diode package structure of claim 1, wherein the circuit structure further comprises an extension layer extending to the second surface, the extension layer covering at least two through holes of the substrate. The light emitting diode package structure of claim 4, wherein the extension layer defines at least two holes corresponding to at least two through holes of the substrate, the at least two holes being filled with solder. The light emitting diode package structure according to any one of claims 1 to 5, wherein at least two through holes of the substrate are provided with a heat conductive material. A manufacturing method of a light emitting diode package structure, the steps comprising:
Providing a substrate having a first surface and a second surface opposite to the first surface, and at least two through holes penetrating the first surface and the second surface, the first surface having an electrical circuit structure;
Fixing a light emitting diode chip on a first surface of the substrate, the light emitting diode chip having solder joints thereon;
The mask layer is disposed on the first surface of the substrate and is disposed on the LED substrate, and the mask layer is provided with an opening corresponding to the solder joint on the LED chip;
Passing the gold wire through the opening of the mask layer and electrically connecting the gold wire to the solder joint of the LED chip and the circuit structure of the substrate;
Fluorescent material is filled between the mask layer and the first surface of the substrate through the through hole of the substrate, and the phosphor material covers the light emitting diode wafer to form a fluorescent layer, and the fluorescent layer is isolated from the gold wire; The protective layer is on the first surface of the substrate and the mask layer and the gold wire cover are disposed in the protective layer. The method for manufacturing a light emitting diode package structure according to claim 7, wherein after the gold wire is electrically connected to the solder joint of the light emitting diode chip and the circuit structure of the substrate, before the fluorescent layer is formed, A step of fixing the sealant layer for the gold wire and the solder joint is provided at the opening of the mask layer. The method for manufacturing a light emitting diode package structure according to claim 7, further comprising the step of forming another sealant layer on the second surface of the substrate corresponding to at least two through holes. The method of manufacturing a light emitting diode package according to any one of claims 7 to 9, further comprising the step of filling a heat conductive material in at least two through holes of the substrate.