Patent Application
20150171296
1. Field of the Invention
The present invention relates to semiconductor packages, and, more particularly to a light emitting package and a carrier structure therefor.
2. Description of the Prior Art
As the technology for developing electronic products is steadily growing, the trend of electronic products has now moved towards low profile, high functionality and high operational speed. Light emitting diode (LED) has the advantages of long life, small size, high resistance to shock, and high energy efficiency, and therefore has been widely used in electronic products requiring illumination, to be used in the industry, incorporated in various electronic products or in home appliances.
Since the conventional LED package 1 utilizes the lead frame 10 as the carrier of the LED element 12, which is at least 0.2 mm in thickness, it makes the LED package 1 too thick to be a desirable candidate as a satisfactory low profile package.
Moreover, the thermal resistance is correlated with the thickness of the package. In specific, the thinner the package is, the less the heat resistance becomes, and the heat transmission is more efficient, as described in R=L/kA (R is heat resistance; K is the transmission distance, i.e., the thickness L of the lead frame; A is the heat transmission area; k is the heat transmission coefficient). Since the overall thickness of the LED package 1 cannot be reduced due to the lead frame 10, the heat resistance also cannot be lowered further, and, as a result, the heat transmission rate cannot be improved.
Therefore, there is an urgent need in solving the foregoing problems.
In light of the foregoing drawbacks of the prior art, the present invention provides a carrier structure, comprising: a plurality of conductive traces each having a first surface, a second surface opposing the first surface, and a side surface abutting the first and second surfaces; an insulative portion combined with the conductive traces to form a packaging substrate; and a receiving body formed on the packaging substrate and having an opening for the first surfaces of the conductive traces to be exposed therefrom.
The present invention further provides a light emitting package, comprising: a plurality of conductive traces each having a first surface, a second surface opposing the first surface, and a side surface abutting the first and second surfaces; an insulative portion combined with the conductive traces to form a packaging substrate; a receiving body formed on the substrate and having an opening for the first surfaces of the conductive traces to be exposed therefrom; at least a light emitting member disposed on the substrate via the opening and electrically connected with the conductive traces; and an encapsulant formed in the opening to encapsulate the light emitting member.
In the light emitting package and the carrier structure, the conductive traces combined with the insulative portion are used to carry the light emitting diode thereon. Therefore, the lead frame provided by the conventional technology is omitted, and the light emitting package and the carrier structure meet the low profile requirement, and the heat transmission efficiency is also enhanced.
Moreover, the design of the insulative portion combined with the conductive traces further strengthen the structural integrity to support the light emitting members.
The present invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein:
The present invention is described in the following with specific embodiments, so that one skilled in the pertinent art can easily understand other advantages and effects of the present invention from the disclosure of the present invention.
It is to be understood that the scope of the present invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements. The scope of the claims, therefore, should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements. In addition, words such as “on,” “top” and “a” are used to explain the preferred embodiment of the present invention only and should not limit the scope of the present invention.
The conductive traces 20 each has a first surface 20a, a second surface 20b opposing the first surface 20a, and a side surface 20c abutting the first surface 20a and the second surface 20b. The conductive traces 20 each is in a convex-concave structure (the same as the convex part 200 of the second surface 20b). The conductive traces 20 are made of a conventional material applicable to form the circuits of the circuit board, such as metal (commonly, copper). The variety of applicable materials is large and is not specifically limited.
In the carrier structure 2a shown in
The receiving body 21 is formed on the insulative portion 25 and a portion of the first surface 20a of each of the conductive traces 20, and has an opening 210 for the first surfaces 20a to be exposed therefrom, such that the receiving body 21 acts as a reflector. In an embodiment, the receiving body 21 is made of silicon or epoxy resin without containing glass fibers.
The light emitting member 22 is disposed on a packaging substrate formed by the conductive traces 20 combined with the insulative portion 25 via the opening 210 of the first surface 20a, and is electrically connected to the conductive traces 20 via a plurality of bonding wires 220.
The insulative portion 25′ of the carrier structure 2a′ shown in
The first insulative layer 251 is made of a dielectric material such as epoxy resin containing glass fibers or cloth. The second insulative layer 252 is a solder mask layer.
As shown in
As shown in
In an embodiment, the conductive traces 20 and the insulative portion 25, 25′, 25″ are fabricated under the substrate process, by using the conductive traces 20 combined with the insulative portion 25, 25′, or 25″ as the carrier of the light emitting member 22. Since the thickness t of each of the conductive traces 20 is very small (0.035 mm), the overall thickness T (at least 0.325 mm) of the light emitting package 2, 2′, 2″ can be reduced, thereby desirably achieving the low profile requirement.
Moreover, since the thickness of each of the conductive traces 20 can be reduced according to the requirement, the heat resistance can also be reduced, so as to increase the heat transmission efficiency.
In addition, supporting strength of the packaging substrate formed by the conductive traces 20 combined with the insulative portion 25, 25′, 25″ to carry the light emitting member 22 is greatly enhanced through secured attachment to the insulative portion 25, 25′, 25″ against the side surfaces 20c of the conductive traces 20.
Furthermore, since the insulative portion 25, 25′, 25″ contains a solder mask material, moist can be prevented from entering the receiving body 21, and therefore it is possible to prevent the inner circuits from corrosion.
In the light emitting package 3, 3′, 3″ (or carrier structure 3a, 3a′, 3a″) shown in
In an embodiment, as shown in
As shown in
As shown in
As shown in
In an embodiment, packaging substrate formed by the conductive traces 20 combined with the insulative portion (not designated by a reference numeral) is used to carry the light emitting member 22, so as to reduce the distance D between two electrical connecting pads 201, 202 of the conductive trace 20, and the carrier structure 2a can be used in the flip-chip fabricating process. In comparison with a conventional lead frame, which cannot be used in the flip-chip fabricating process, the carrier structure 2a according to the present invention can be used in various applications.
In an embodiment, an additional layer (e.g., a surface treatment surface) can be formed on the conductive traces 20. The surface treatment layer includes gold, silver, tin, and/or organic solderability preservative (OSP).
In summary, the light emitting package and the carrier structure according to the present invention utilize the conductive trace to replace the conventional lead frame as the carrier for light emitting members, such that it is possible to meet the low profile requirement as well as to increase heat transmission efficiency. Moreover, supporting strength for the packaging substrate formed by the conductive traces combined with the insulative portion to carry the light emitting member is greatly enhanced through secured attachment to the insulative portion against the conductive traces.
The present invention has been described using exemplary preferred embodiments. However, it is to be understood that the scope of the present invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements. The scope of the claims, therefore, should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102223444 | Dec 2013 | TW | national |
