Package structure and LED package structure

A package structure includes a base unit, a pin unit and a housing unit. The base unit has a carrier member and a through hole penetrating through the carrier member, and at least one annular structure is formed in the through hole. The pin unit has a plurality of conductive pins disposed beside the carrier member. The housing unit has an annular housing encircling the carrier member to envelop one part thereof and connecting to the pin unit, and the annular housing is partially filled into the through hole to cover the annular structure. Therefore, the instant disclosure can increase the bonding force between the carrier member and the annular housing and retard external moisture to permeate through slits between the carrier member and the annular housing to intrude into the chip-mounting region, thus the reliability and the usage life are increased.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The instant disclosure relates to a package structure and an LED package structure, in particular, to a package structure and an LED package structure to enhance the structural strength and retard external moisture to intrude into chip-mounting region.

2. Description of Related Art

In general, LED (Light-Emitting Diode) has some advantages better than a traditional light source, such as small size, power saving, excellent light efficiency, long life, high-speed modulation response and mercury free. In recent years, the LED has been widely used in several applications and entered into everyone's daily life. Hence, the traditional lighting source has been replaced by LED with high brightness such as a high power LED due to the progress of high technology.

In addition, the high power LED will generate more high heat, thus the traditional package structure needs to use large slug to dissipate the heat. However, when pre-molding package gel (plastic material) adheres the slug (metal), the bonding force (the structural strength) between the package gel and the slug is bad. Furthermore, the traditional package structure usually has some slits between the package gel and the slug, and external moisture will permeate through the slits to intrude into chip-mounting region of the LED, thus the chip-mounting region will be rusted.

SUMMARY OF THE INVENTION

In view of the aforementioned issues, the instant disclosure provides a package structure and an LED package structure to enhance the structural strength and retard external moisture to intrude into chip-mounting region.

To achieve the above-mentioned objectives, the instant disclosure provides a package structure, including a base unit, a pin unit and a housing unit. The base unit has a carrier member and at least one through hole penetrating through the carrier member, and at least one annular structure is formed in the at least one through hole. The pin unit has a plurality of conductive pins disposed beside the carrier member. The housing unit has an annular housing encircling the carrier member to envelop one part thereof and connecting to the pin unit, and the annular housing is partially filled into the at least one through hole to cover the at least one annular structure.

Moreover, the instant disclosure further provides an LED package structure that adds a light-emitting unit and a package unit to the package structure. The light-emitting unit has a plurality of LED chips disposed on the carrier member and being surrounded by the annular housing, and each of the LED chips is electrically connected between any two of the conductive pins. The package unit has a light-transmitting package body covering the LED chips and being surrounded by the annular housing.

Therefore, the instant disclosure can enhance the bonding force between the carrier member and the annular housing, and retard external moisture to permeate through slits between the carrier member and the annular housing to intrude into the chip-mounting region, thus the reliability and the usage life are enhanced.

To further understand the techniques, means and effects the instant disclosure takes for achieving the prescribed objectives, the following detailed descriptions and appended drawings are hereby referred, such that, through which, the purposes, features and aspects of the instant disclosure can be thoroughly and concretely appreciated; however, the appended drawings are merely provided for reference and illustration, without any intention to be used for limiting the instant disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1A to 1Dshow a package structure according to the first embodiment of the instant disclosure. The package structure of the first embodiment includes a base unit1, a pin unit2and a housing unit3.

Referring toFIG. 1A, it shows a schematic view of the relative position of the base unit1and the pin unit2. In addition,FIG. 1Bshows a cross-sectional view of the A part inFIG. 1A.

Moreover, the base unit1has a carrier member10and at least one through hole11penetrating through the carrier member10. The carrier member10is usually made of metal material with high thermal conductivity coefficient. The carrier member10has a chip-mounting region100formed on a top surface thereof, and at least one annular structure110is formed in the through hole11, i.e. the annular structure110is formed on an inner surface of the through hole11. The carrier member10may be a one-piece heat-dissipating element in this embodiment. The carrier member10may be a two-piece structure in another embodiment. For example, the carrier member10has a carrier body (not shown) and a heat-dissipating layer (not shown) extended from the top surface of the carrier body to the bottom surface of the carrier body.

The barrier member10has a plurality of lateral projections10aready to be encapsulated by the housing unit3. For example, the carrier member10has four sides (as shown inFIG. 1A) in the first embodiment. The lateral projections10amay be disposed on the same side, on any two adjacent sides, on any two opposite sides, on any three sides or on the four sides. Of course, in another embodiment, the lateral projections10amay be omitted, or the lateral projections10amay be replaced by many lateral trenches (not shown), by at least one annular lateral trench (not shown) encircling a lateral periphery of the carrier member10or at least one continuous annular lateral projection (not shown). In other words, if designer uses many lateral projections10aor many lateral trenches (not shown), the lateral projections10aor the lateral trenches (not shown) may be selectively disposed on one or more sides of the carrier member10; If designer uses the annular lateral trench (not shown) or at least one annular lateral projection (not shown), at least one annular lateral trench (not shown) or at least one annular lateral projection (not shown) may surround the whole side of the carrier member10.

The carrier member10has a plurality of front trenches10bthat are formed on a top surface thereof and ready to be encapsulated by the housing unit3. Of course, in another embodiment, the front trenches10bmay be omitted, or the front trenches10bmay be replaced by many front projections (not shown). In addition, many front trenches (not shown) or front projections (not shown) may be formed on the bottom surface of the carrier member10and ready to be encapsulated by the housing unit3according to different requirements.

The carrier member10has a plurality of union support structures10cready to be encapsulated by the housing unit3and extended outwards from the carrier member10and a plurality of projection structures10dready to be encapsulated by the housing unit3and correspond to the union support structures10c. In addition, each of the union support structures10chas a union cutting plane100cformed on an end thereof and exposed from the housing unit3, and each of the projection structures10dis adjacent to each of the union support structures10cand is extended outwards from a corner of the carrier member10. In other words, the four projection structures10dare projected from four corners of the carrier member10for enhancing a contact path between the side of the carrier member10and the housing unit3.

For example, the carrier member10has four sides, four union support structures10c(two pairs of union support structures10c) and four projection structures10d(two pairs of projection structures10d) as shown inFIG. 1A.

The two pairs of union support structures10care respectively disposed on two opposite sides of the carrier member10, thus two of the union cutting planes100care exposed from one side of the carrier member10as shown inFIG. 1C.

The four projection structures10dare respectively connected to the four union support structures10c, and the two pairs of projection structures10dare respectively projected from another two opposite sides of the carrier member10. In addition, each of the four projection structures10dand each four union support structures10care adjacent to each other to form a predetermined included angle between the projection structure10dand the union support structure10c. When the included angle is close to 90 degrees, each of the union support structures10cand each of the projection structures10dare connected to form a structure similar to an L shape.

Of course, the another embodiment may provide two union support structures10crespectively disposed on two opposite sides of the carrier member10, and each of the union support structures10cis disposed on a center of each side of the carrier member10to obtain a balance effect for the carrier member10. When only two union support structures10crespectively disposed on the two opposite sides of the carrier member10, it would be best for each of the union support structures10cto use two projection structures10dthat are respectively disposed beside the two opposite sides of each of the union support structures10cand respectively projected from two corresponding corners of the carrier member10(it means the four projection substrates10dare respectively projected from the four corners of the carrier member10).

Furthermore, the pin unit2has a plurality of conductive pins20disposed beside the carrier member10. For example, the conductive pins20may be disposed beside the same side of the carrier member10or may be typically disposed beside two opposite side of the carrier member10. In the first embodiment,FIG. 1Ashows eight conductive pins20that are typically disposed beside two opposite side of the carrier member10(there are four conducive pins20beside each of the sides of the carrier member10). Each of the conductive pins20has at least one inside pin hole20aready to be filled with the housing unit3. Of course, the inside pin hole20amay be omitted in the first embodiment. In addition, each of the conductive pins20has at least one pin trench200ready to be encapsulated by the housing unit3. For example, each of the conductive pins20has two pin trenches200formed on a top surface thereof in the first embodiment. Of course, one or more trench structures may be formed on the top surface, the bottom surface or the side of each of the conductive pins20in other embodiments. In addition, the pin trenches200may be omitted in the instant disclosure, or the pin trenches200may be replaced by many pin projections (not shown). Besides, each of the conductive pins20has at least one outside pin hole20b.

Referring toFIG. 1B, it shows across-sectional view of the A part inFIG. 1A. The annular structure110may be an inner projection in the first embodiment. In other words, the inner projection has an annular appearance and formed on the inner surface of the through hole11, and the cross-sectional view of the through hole11inFIG. 1Bshows as a I-shaped hole. Of courser, the inner projection may be replaced by an inner trench (not shown), thus the cross-sectional view of the through hole11would show as a crisscross appearance.

FIG. 1Cshows a schematic view of the package structure according to the first embodiment of the instant disclosure.FIG. 1Dshows a partial, view of the package structure according to the first embodiment of the instant disclosure. Comparing withFIG. 1A,FIGS. 1C and 1Dadd the housing unit3to partially envelop the base unit1and the pin unit2.

The housing unit3is usually made of plastic material such as opaque and reflective plastic material. The housing unit3has an annular housing30encircling the carrier member10to envelop one part thereof and connecting to the pin unit2. The annular housing30is partially filled into the through hole11(it means the through hole11is filled with or encapsulated by one part of the annular housing30) to cover the annular structure110as shown inFIGS. 1A and 1B. In addition, the annular housing30has a encircling housing30asurrounding the carrier member10and at least two extending housings30bextended from an inner surface300of the encircling housing30ato the carrier member10to envelop a top surface of the carrier member10. For example, the annular housing30surrounds a peripheral portion (not shown) of the carrier member10and envelops one part of the carrier member10to expose partially a top surface of the carrier member10and a bottom surface of the carrier member10. The peripheral portion is a periphery of the carrier member10enveloped by the annular housing30, as shown inFIG. 1D. The annular housing30surrounds the peripheral portion of the carrier member10and envelops one part of each of the conductive pins20to expose a first end portion203of each of the conductive pins20and a top surface of the second end portion204of each of the conductive pins20. The top surface of the second end portion204may be a wire-bonding region for achieving electrical connection.

Hence, when the carrier member10is encapsulated by the annular housing30, the lateral projections10a, the front trenches10b, the union support structures10cand the projection structures10dof the carrier member10are encapsulated by the annular housing30and the union cutting plane100cis exposed out of the annular housing30. In addition, after each of the conductive pins20is encapsulated by the annular housing30, the inner pin hole20aof each of the conductive pins20are filled with the annular housing30and the pin trenches200are encapsulated by the annular housing30. Each of the outside pin holes20bis divided into a first hole portion201adjacent to the carrier member10and a second hole portion202connecting the first hole portion201. The first hole portion201of each of the conductive pins20is filled with one part of the annular housing30, and the second hole portion202of each of the conductive pins20is exposed from the annular housing30.

The package structure of the instant disclosure may be used for any type of light-emitting chip such as LED chip. For example, referring toFIG. 2, it shows a partial cross-sectional view of the LED package structure according to the first embodiment of the instant disclosure. The LED package structure of the instant disclosure includes a base unit1, a pin unit2, a housing unit3, a light-emitting unit4and a package unit5. The difference betweenFIG. 2andFIG. 1Dis thatFIG. 2adds the light-emitting unit4, the package unit5and two conductive wires W.

The light-emitting unit4has a plurality of LED chips40(only one LED chip40is disclosed inFIG. 2for example) disposed on the carrier member10and being surrounded by the annular housing30. Each of the LED chips40is electrically connected between any two of the conductive pins20. For example, each of the LED chips40is electrically connected between any two of the conductive pins20by at least two conductive wires W, thus the current path from any one conductive pin20to the LED chip40differs from the heat-dissipating path from the LED chip40to the carrier member10. In other words, because the LED chip40is a horizontal chip, the conductive path and the heat-dissipating path are separated from each other.

Of course, the LED chip40may be a vertical chip, thus the conductive path and the heat-dissipating path are the same. In other words, the first embodiment can take one conductive wire W to electrically connect between the carrier member10and one conductive pin20(one electrode of the LED chip40contacts the carrier member10) and take another conductive wire W to electrically connect between the LED chip40and another conductive pin20(another electrode of the LED chip40contacts the conductive wire W). Hence, the LED chip40may be electrically connected between any two of the conductive pins20by the method of combining the conductive path and the heat-dissipating path.

If the instant disclosure uses many LED chips40at the same time according to different requirements, the LED chips40may be selectively electrically connected between any two of the conductive pins20in parallel or in series. Of course, the LED chips40may be electrically connected between any two of the conductive pins20in parallel and in series at the same time. In addition, the package unit5has a light-transmitting package body (such as transparent gel or phosphor gel) covering the LED chips40and being surrounded by the annular housing30.

In conclusion, the instant disclosure has at least one advantage shown as follows:

Because the instant disclosure provides the design of filling one part of the annular housing30into the through hole11, the instant disclosure can increase the bonding force between the carrier member10and the annular housing30, and retard external moisture to permeate through slits between the carrier member10and the annular housing30to intrude into the chip-mounting region100. In addition, the instant disclosure may specially strengthen the structural strength between pre-mold and metal slug to retard external moisture due to the design of forming the annular structure110on the inner surface of the through hole11.

Because the instant disclosure provides the design of forming the lateral projections10aon the side of the barrier member10, the instant disclosure can increase the bonding force between the carrier member10and the annular housing30, and extend path to retard external moisture to permeate through slits between the carrier member10and the annular housing30to intrude into the chip-mounting region100.

Because the instant disclosure provides the design of forming the front trenches10bon the top surface and/or the bottom surface of the barrier member10, the instant disclosure can increase the bonding force between the top surface and/or the bottom surface of the carrier member10and the annular housing30, and retard external moisture to permeate through slits between the carrier member10and the annular housing30to intrude into the chip-mounting region100.

Because the instant disclosure provides the design of forming the projection structures10dready to be encapsulated by the housing unit3and correspond to the union support structures10c, the instant disclosure can extend path to retard external moisture to permeate through slits between the union support structures10cof the carrier member10and the annular housing30to intrude into the chip-mounting region100.

The instant disclosure provides the designs of filling one part of the annular housing30into the first hole portion201of each of the conductive pins20and exposing the second hole portion202of each of the conductive pins20therefrom to reduce the contact area between the annular housing30and each of the conductive pins20, thus instant disclosure can retard external moisture to permeate through slits between the annular housing30and each of the conductive pins20to intrude into the chip-mounting region100.

Because the instant disclosure provides the design of forming the at least two extending housings30bthat are extended from the inner surface300of the encircling housing30ato the carrier member10to envelop the top surface of the carrier member10, the instant disclosure can increase the bonding force between the top surface of the carrier member10and the annular housing30, and enlarge contact area between package unit5and the annular housing30. Therefore, the instant disclosure can decrease the probability of separating the annular housing30from the carrier member10and decrease the contact area between the package unit5and the carrier member10to decrease the probability of separating the package unit5from the carrier member10made of metal due to the low bonding force between the package unit5and the metal carrier.

Referring toFIGS. 3A to 3F, the second embodiment of the instant disclosure shows six LED package structures using different wire-bonding methods, thus the instant disclosure also can provide the LED package structure with six conductive pins20.FIG. 3Adiscloses that each of the LED chips40is electrically connected between every two symmetrical or asymmetric conductive pins20.FIG. 3Bdiscloses that each of the LED chips40is electrically connected between every two symmetrical or asymmetric conductive pins20.FIG. 3Cdiscloses that two LED chips40are collectively electrically connected between two symmetrical or asymmetric conductive pins20.FIG. 3Ddiscloses that every two LED chips40are electrically connected in series between two symmetrical or asymmetric conductive pins20.FIG. 3Ediscloses that an LED chip40is electrically connected between two symmetrical or asymmetric conductive pins20.FIG. 3Fdiscloses that two LED chips40are electrically connected between two symmetrical or asymmetric conductive pins20.

Furthermore, in general, there are two types of the LED chips including horizontal type and vertical type. The horizontal LED chip has at least two electrodes disposed on a top surface thereof, and the vertical LED chip has at least two electrode respectively disposed on a top surface and a bottom surface thereof. The LED chips40of the instant disclosure can be horizontal LED chips that are applied to the above-mentioned wire-bonding methods as shown inFIGS. 3A to 3F. However, in another embodiment, if the LED chip40inFIG. 3Eis a vertical LED chip, one conductive wire W is only changed to electrically connect between the conductive pin20and the carrier member10to achieve electrical connection effect for the LED chip40.

Moreover, in another embodiment, when using many LED chips40, the LED chips40may be selected from horizontal LED chips and vertical LED chips. In addition, the former description of electrically connecting each of the LED chips40between two conductive pins20is just an example not to limit the instant disclosure. In other words, the designer not only can use the LED chips40of different numbers and types (such as using single horizontal LED chip or single vertical LED chip, or using the horizontal LED chip and the vertical LED chip at the same time), but also can electrically connect the LED chips40in parallel, in series or in parallel and series.

The above-mentioned descriptions represent merely the preferred embodiment of the instant disclosure, without any intention to limit the scope of the instant disclosure thereto. Various equivalent changes, alternations or modifications based on the claims of instant disclosure are all consequently viewed as being embraced by the scope of the instant disclosure.