LED chip package structure using a ceramic material as a substrate and a method for manufacturing the same

An LED chip package structure using a ceramic material as a substrate includes a ceramic substrate, a conductive unit, a hollow ceramic casing, a plurality of LED chips, and a package colloid. The ceramic substrate has a main body, and a plurality of protrusions extended from three faces of the main body. The conductive unit has a plurality of conductive layers formed on the protrusions, respectively. The hollow casing is fixed on a top face of the main body to form a receiving space for exposing a top face of each conductive layer. The LED chips are received in the receiving space, and each LED chip has a positive electrode side and a negative electrode side respectively and electrically connected to different conductive layers. In addition, the packaging colloid is filled into the receiving space for covering the LED chips.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an LED chip package structure and a method for manufacturing the same, and particularly relates to an LED chip package structure using a ceramic material as a substrate and a method for manufacturing the same.

2. Description of the Related Art

FIG. 1shows a cross-sectional, schematic view of a vertical LED chip package structure of the prior art. The vertical LED chip package structure includes an insulative substrate1a, a lead frame2a, an LED chip3a, and a fluorescent colloid4a.

The lead frame2ahas two conductive pins20a,21arespectively extended along two opposite lateral sides and bent twice, so that the bottom faces of the two conductive pins20a,21aare electrically connected with a PCB5a. In addition, the conductive pin20ahas a positive electrode area200a, and the conductive pin21ahas a negative electrode area210a.

Moreover, the LED chip3ahas a positive electrode side300aand a negative electrode side310a. The LED chip3ais disposed on the conductive pin20adirectly, so that the positive electrode side300aof the LED chip3ais electrically connected with the positive electrode area200aof the conductive pin20adirectly. The negative electrode side310aof the LED chip3ais electrically connected with the negative electrode area210aof the conductive pin21avia a leading wire6a.

The fluorescent colloid4ais covered on the LED chip3afor protecting the LED chip3a. Therefore, the vertical LED chip package structure should project light upwardly (such as the arrows inFIG. 1).

FIG. 2shows a perspective, schematic view of a horizontal LED chip package structure of the prior art, andFIG. 3shows a cross-sectional view along line3-3of a horizontal LED chip package structure shown inFIG. 2. The horizontal LED chip package structure includes an insulative substrate1b, a lead frame2b, an LED chip3b, and a fluorescent colloid4b.

The lead frame2bhas two conductive pins20b,21brespectively extended along one lateral side and bent twice, so that the bottom faces of the two conductive pins20b,21bare electrically connected with a PCB5b. In addition, the conductive pin20bhas a positive electrode area200b, and the conductive pin21bhas a negative electrode area210b.

Moreover, the LED chip3bhas a positive electrode side300band a negative electrode side310b. The LED chip3bis disposed on the conductive pin20bdirectly, so that the positive electrode side300bof the LED chip3bis electrically connected with the positive electrode area200bof the conductive pin20bdirectly. The negative electrode side310bof the LED chip3bis electrically connected with the negative electrode area210bof the conductive pin21bvia a leading wire6b.

The fluorescent colloid4bis covered on the LED chip3bfor protecting the LED chip3b. Therefore, the horizontal LED chip package structure should project light sideward (such as the arrows inFIG. 3).

However, if the conductive pins (20a,21a,20b,21b) want to electrically connect with the PCB (5a,5b), the conductive pins (20a,21a,20b,21b) need to be bent twice. Therefore, the complexity of the manufacturing process in the prior art should be increased.

SUMMARY OF THE INVENTION

One particular aspect of the present invention is to provide an LED chip package structure using a ceramic material as a substrate and a method for manufacturing the same. The advantage of the present invention is that a conductive layer is formed on a ceramic substrate via any forming method, and a hollow ceramic casing is fixed on a top face of the ceramic substrate via an LTCC (Low-Temperature Cofired Ceramics). Therefore, the LED chip package structure of the present invention can electrically connect with a PCB easily without bending the conductive pins as the prior art.

In order to achieve the above-mentioned aspects, the present invention provides an LED chip package structure using a ceramic material as a substrate, comprising: a ceramic substrate, a conductive unit, a hollow ceramic casing, a plurality of LED chips, and a package colloid. The ceramic substrate has a main body, and a plurality of protrusions separated from each other and respectively extended from three faces of the main body. The conductive unit has a plurality of conductive layers formed on the protrusions, respectively. The hollow ceramic casing is fixed on a top face of the main body to form a receiving space for exposing a top face of each conductive layer. The LED chips are received in the receiving space, and each LED chip has a positive electrode side and a negative electrode side respectively and electrically connected to different conductive layers. The package colloid is filled into the receiving space for covering the LED chips.

In order to achieve the above-mentioned aspects, the present invention provides a method for manufacturing an LED chip package structure that uses a ceramic material as a substrate, comprising: providing a ceramic substrate that has a main body, and a plurality of protrusions separated from each other and respectively extended from three faces of the main body; forming a plurality of conductive layers on the protrusions, respectively; fixing a hollow ceramic casing on a top face of the main body to form a receiving space for exposing a top face of each conductive layer; receiving a plurality of LED chips in the receiving space, wherein each LED chip has a positive electrode side and a negative electrode side respectively and electrically connected to different conductive layers; and filling a package colloid into the receiving space for covering the LED chips.

Moreover, the conductive unit further comprises a first conductive unit, a hardness-strengthening unit, and a second conductive unit. The first conductive unit has a plurality of first conductive layers respectively formed on the protrusions. The hardness-strengthening unit has a plurality of hardness-strengthening layers respectively formed on the first conductive layers. The second conductive unit has a plurality of second conductive layers respectively formed on the hardness-strengthening layers. Therefore, the first conductive layers, the hardness-strengthening layers, and the second conductive layers are sequentially assembled together to form the conductive layers.

Alternatively, the conductive unit further comprises: a first conductive unit and a second conductive unit. The first conductive unit has a plurality of first conductive layers respectively formed on the protrusions. The second conductive unit has a plurality of second conductive layers respectively formed on the first conductive layers, and each second conductive layer is a hardness-strengthening layer. Therefore, the first conductive layers and the second conductive layers are sequentially assembled together to form the conductive layers.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed. Other advantages and features of the invention will be apparent from the following description, drawings and claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIGS. 4 to 6, the first embodiment of the present invention provides a method for manufacturing an LED chip package structure that uses a ceramic material as a substrate. The steps of the method comprises: firstly, referring toFIGS. 5A and 6, providing a ceramic substrate1that has a main body10, and a plurality of protrusions11separated from each other and respectively extended from three faces of the main body10(S100). The ceramic substrate1further has a plurality of half through holes12formed on a lateral side of the main body10and respectively between each two protrusions11.

Moreover, the method further comprise: forming a plurality of first conductive layers2on the protrusions11, respectively (S102), forming a plurality of hardness-strengthening layers3on the first conductive layers2, respectively (S104), and then forming a plurality of second conductive layers4formed on the hardness-strengthening layers3, respectively (S106). In addition, each first conductive layer2can be a silver paste layer, each hardness-strengthening layer3can be a nickel layer, and each second conductive layer4can be a gold layer or a silver layer. Furthermore, the first conductive layers2, the hardness-strengthening layers3, and the second conductive layers4are sequentially assembled together to form a plurality of conductive layers. Hence, the steps of S104to S106mean that forming the conductive layers on the protrusions11, respectively.

Referring toFIGS. 5B and 6, the method further comprises: fixing a hollow ceramic casing5on a top face of the main body10of the ceramic substrate1to form a receiving space50for exposing a top face of each second conductive layer4(S108). The main body10and the hollow ceramic casing5are two cuboids that are mated with each other, and the hollow ceramic casing5is fixed on the top face of the main body10via an LTCC (Low-Temperature Cofired Ceramics).

Referring toFIGS. 5C and 6, the method further comprises: receiving a plurality of LED chips6in the receiving space50, and each LED chip6having a positive electrode side and a negative electrode side respectively and electrically connected to different second conductive layers4(S110). The positive electrode side and the negative electrode side of each LED chip6are electrically connected to different second conductive layers4via two leading wires7. Finally, the method comprises filling a package colloid8into the receiving space50for covering the LED chips6(S112). Therefore, the receiving space50faces top, so that bottom sides of the second conductive layers4contact with a PCB (not shown). Hence, the LED chip package structure should project light upwardly in a vertical status (such as the arrows inFIG. 6).

FIG. 7shows a lateral, schematic view of a first arrangement of a plurality of LED chips according to the present invention. The second conductive layers4are divided into a plurality of positive electrode portions40and negative electrode portions41. The positive electrode side60and the negative electrode side61of each LED chip6are arranged on an upper surface of each LED chip6. Therefore, the positive electrode side60and the negative electrode side61of each LED chip6are respectively and electrically connected with the adjacent positive and negative electrode portions40,41via two leading wires41by a wire-bounding method.

FIG. 8shows a lateral, schematic view of a second arrangement of a plurality of LED chips according to the present invention. The second conductive layers4′ are divided into a plurality of positive electrode portions40′ and negative electrode portions41′. The positive electrode side60′ and the negative electrode side61′ of each LED chip6′ are respectively arranged on a lower surface and an upper surface of each LED chip6′. Therefore, the positive electrode side60′ of each LED chip6′ is directly and electrically connected with the corresponding positive electrode portion40′, and the negative electrode side61′ of each LED chip6′ is electrically connected with the corresponding negative electrode portion41′ via a leading wire7′ by a wire-bounding method.

FIG. 9shows a lateral, schematic view of a third arrangement of a plurality of LED chips according to the present invention. The second conductive layers4″ are divided into a plurality of positive electrode portions40″ and negative electrode portions41″. The positive electrode side60″ and the negative electrode side61″ of each LED chip6″ are arranged on a lower surface of each LED chip6″. Therefore, the positive electrode side60″ and the negative electrode side61″ of each LED chip6″ are respectively and electrically connected with the adjacent positive and negative electrode portions40″,41″ via a plurality of corresponding solder balls7″ by a flip-chip method.

FIG. 10shows a lateral, schematic view of a fourth arrangement of a plurality of LED chips according to the present invention. The positive electrode side90and the negative electrode side91of each LED chip9are arranged on an upper surface of each LED chip9, and each LED chip9is disposed between each two protrusions92. Therefore, the positive electrode side90and the negative electrode side91of each LED chip9are respectively and electrically connected with the adjacent positive and negative electrode portions94,95via two leading wires93by a wire-bounding method.

Referring toFIGS. 11 and 12, the second embodiment of the present invention provides a method for manufacturing an LED chip package structure that uses a ceramic material as a substrate. The steps of S200-S202and S206-S210in the second embodiment are same as the steps of S100-S102and S108-S112in the first embodiment. The differences between the second embodiment and the first embodiment is that after the step of S202, the method comprises forming a plurality of second conductive layers3′ on the first conductive layers2, and each second conductive layer3′ being a hardness-strengthening layer (S204). Furthermore, the first conductive layers2and the second conductive layers3′ are sequentially assembled together to form a plurality of conductive layers. Hence, the steps of S202to S204mean that forming the conductive layers on the protrusions11, respectively.

FIG. 13shows a perspective, schematic view of an LED chip package structure in a horizontal status according to the second embodiment of the present invention. The receiving space50faces lateral, so that lateral sides of the second conductive layers3′ contact with a PCB (not shown). Hence, the LED chip package structure should project light sideward in a horizontal status (such as the arrows inFIG. 12).

In conclusion, the advantage of the present invention is that the conductive layers is formed on the ceramic substrate1via any forming method, and the hollow ceramic casing5is fixed on the top face of the ceramic substrate1via an LTCC (Low-Temperature Cofired Ceramics). Therefore, the LED chip package structure of the present invention can electrically connect with a PCB (not shown) easily without bending the conductive pins (20a,21a,20b,21b) as the prior art.