TWI626774B - Led leadframe and led package structure - Google Patents

Abstract

The invention relates to an LED bracket and an LED package structure using the same. The LED bracket includes: an insulating substrate, first and second electrode pads. The insulating substrate is formed with a cup-shaped solid crystal region and a strip-shaped insulating portion located in the cup-shaped solid crystal region, and the first and second electrode pads are fixed on the insulating substrate and are spaced apart from each other by a strip-shaped insulating portion. At the bottom of the solid crystal region, the strip-shaped insulating portion has at least one bend in the cup-shaped solid crystal region. The invention adopts the structural design of the electrode pad on the LED bracket, so that one of the electrode pads, for example, the positive electrode pad, has a size sufficient for the wire bonding machine wire or a pole nano diode wafer, so that the other electrode is drained. It may be large, so that the LED chips can be symmetrically distributed on the LED bracket, thereby achieving the purpose of increasing the luminous efficiency and heat dissipation effect of the wafer.

Description

LED bracket and LED package structure

The present invention relates to the field of LED technologies, and in particular, to an LED bracket and an LED package structure.

The LED (Light Emitting Diode) bracket generally includes: an insulating substrate, a positive electrode pad, and a negative electrode pad; wherein the insulating substrate is typically centrally provided with a solid crystal region, and the positive electrode pad and the negative electrode pad are fixed at The insulating substrate is located at the bottom of the solid crystal region at a distance from each other, and an area of the negative electrode pad in the solid crystal region is larger than an area of the positive electrode pad in the solid crystal region. When such an LED holder is applied to an LED chip package, the LED chip is fixed on the negative electrode pad in the solid crystal region and connected to the positive electrode pad and the negative electrode pad by wire bonding.

However, since the area of the conventional positive electrode pad in the solid crystal region is too large, the LED chip cannot be placed in the center of the solid crystal region during the LED chip packaging process, which causes the luminous efficiency of the LED wafer to be lowered; The area of the positive electrode pad in the solid crystal region is large, and the area of the negative electrode pad in the solid crystal region is reduced, and the LED chips are all placed on the negative electrode pad, which reduces the heat dissipation effect on the LED chip.

Therefore, in order to overcome the defects and deficiencies in the prior art, the present invention provides an LED bracket and an LED package structure to improve the luminous efficiency and heat dissipation effect of the wafer.

Specifically, an LED bracket provided by an embodiment of the present invention includes: an insulating substrate, a first electrode pad, and a second electrode pad. The insulating substrate is formed with a cup-shaped solid crystal region and a strip-shaped insulating portion located in the cup-shaped solid crystal region, and the first electrode pad and the second electrode pad are fixed on the insulating substrate and The strip-shaped insulating portion has at least one bend in the cup-shaped solid crystal region by the strip-shaped insulating portion spaced apart at a bottom of the cup-shaped solid crystal region.

In an embodiment of the invention, the strip-shaped insulating portion has a plurality of the bent portions in the cup-shaped solid crystal region.

In an embodiment of the present invention, the strip-shaped insulating portion includes two straight segments and an arc portion connected between the two straight segments in the cup-shaped solid crystal region, the first The electrode pad has a concave curved portion on a side of the bowl-shaped solid crystal region adjacent to the strip-shaped insulating portion, and the second electrode pad is adjacent to the strip in the cup-shaped solid crystal region One side of the insulating portion correspondingly has a convex arc portion.

In an embodiment of the invention, the strip-shaped insulating portion is formed of three straight segments connected in series in the cup-shaped solid crystal region and is substantially U-shaped.

In an embodiment of the invention, the strip-shaped insulating portion is formed by two connected straight segments in the cup-shaped solid crystal region and has a bent portion so as to be substantially L-shaped.

In an embodiment of the invention, an area ratio of the first electrode pad and the second electrode pad in the cup-shaped solid crystal region of the bowl is 1:3 to 1:5.

In one embodiment of the invention, the width of the first electrode pad in the cup-shaped solid crystal region of the bowl is from 0.15 mm to 0.3 mm.

In an embodiment of the invention, the junction of the first electrode pad and the insulating substrate and the junction of the second electrode pad and the insulating substrate are stepped.

In addition, an LED package structure according to an embodiment of the present invention includes: at least one LED chip, a package body, and any one of the foregoing LED holders; wherein the at least one LED chip is centrally symmetrically distributed on the bowl of the LED holder. The first electrode pad and the second electrode pad are wire-bonded and fixed on the second electrode pad; the package is filled in the cup-shaped solid crystal region and covers the at least one LED chip.

In an embodiment of the invention, the LED package structure further includes a nano-anode wafer soldered to the first electrode pad and connected to the second electrode pad.

As can be seen from the above, the embodiment of the present invention allows the structure of the electrode pads on the LED holder to be such that one of the electrode pads, such as the positive electrode pad, is of sufficient size to be soldered to the wire bonding machine or to place a nano-anode wafer. Therefore, the other electrode pad is made as large as possible, so that the LED chip can be symmetrically distributed on the LED bracket, thereby achieving the purpose of increasing the luminous efficiency and heat dissipation effect of the wafer.

The above described objects, features and advantages of the present invention will become more apparent from the aspects of the appended claims.

Referring to FIG. 1 , FIG. 2 , FIG. 3 , FIG. 4A and FIG. 4B , an LED holder 10 according to an embodiment of the invention includes an insulating substrate 11 , a positive electrode pad 13 , and a negative electrode pad 15 . The insulating substrate 11 is centrally formed with a cup-shaped solid crystal region 110 and a strip-shaped insulating portion 112 located in the cup-shaped solid crystal region 110; the negative electrode pad 15 and the positive electrode pad 13 are fixed on the insulating substrate 11 and are provided by the strip The insulating portions 112 are spaced apart at the bottom of the cup-shaped solid crystal region 110. Typically, the negative electrode pad 15, the positive electrode pad 13, and the insulating substrate 11 are injection molded integrally formed structures.

As shown in FIG. 3, the strip-shaped insulating portion 112 between the positive electrode pad 13 and the negative electrode pad 15 has a non-straight strip shape and has two bent portions. More specifically, the strip-shaped insulating portion 112 is constituted by two straight portions and an arc portion between the two straight portions in FIG. 3; the positive electrode pad 13 has a concave curved shape on a side adjacent to the strip-shaped insulating portion 112. Accordingly, the negative electrode pad 15 has a convex arc-shaped portion on the side adjacent to the strip-shaped insulating portion 112, that is, the positive electrode pad 13 and the negative electrode pad 15 are complementary in shape in the cup-shaped solid crystal region 110. Furthermore, the width W of the positive electrode pad 13 in the cup-shaped solid crystal region 110 is in the range of 0.15 mm to 0.3 mm, which is sufficient for the wire bonding machine to solder or solder an antistatic Zener diode chip. The area ratio of the positive electrode pad 13 and the negative electrode pad 15 in the cup-shaped solid crystal region 110 is preferably 1:3 to 1:5, and the convex curved portion of the cup negative electrode pad 15 is advantageous for soldering the nano-polar body. The wire bonder does not touch the wafer during the wafer. Here, since the area of the positive electrode pad 13 in the cup-shaped solid crystal region 110 is reduced by the shape design, the area of the negative electrode pad 15 in the cup-shaped solid crystal region 110 is correspondingly increased, and the area of the negative electrode pad 15 is far. Far greater than the positive pad 13, which enables the LED chip 20, such as the model 3030, to be placed symmetrically within the cup-shaped solid crystal region 110 of the LED holder 10 and fixed when the LED holder 10 is applied to the LED chip package. On the negative electrode pad 15, this can increase the excitation efficiency of the phosphor powder, improve the luminous efficiency of the wafer, and the increase in the area of the negative electrode pad 15 in the cup-shaped solid crystal region 110 contributes to better heat dissipation of the LED chip 20.

As shown in FIG. 4A and FIG. 4B, the junction 122 of the positive electrode pad 13 and the insulating substrate 11 is designed to be stepped, and the junction 124 of the negative electrode pad 15 and the insulating substrate 11 is also designed to be stepped, so that the path of moisture penetration can be extended. Increase its air tightness.

5A-5E, which are various examples of applying an LED bracket to an LED chip package according to an embodiment of the present invention. specifically:

In FIG. 5A, the strip-shaped insulating portion 112 is composed of two straight portions and an arc portion between the two straight portions and is located between the positive electrode pad 13 and the negative electrode pad 15, and the two LED chips 20 are, for example, the specification model number 1846. The LED chips are symmetrically disposed in the cup-shaped solid crystal region 110 and are connected to the positive electrode pad 13 and the negative electrode pad 15 and are fixed on the negative electrode pad 15. The two LED chips 20 are arranged horizontally and opposite to the cup cup. The longitudinal dashed lines of the geometric centers of the solid crystal regions 110 (the intersections of the horizontal dashed lines and the longitudinal dashed lines in FIG. 5A) are symmetrically distributed, and the geometric center of each of the LED wafers 20 is located substantially at the geometric center of the cup-shaped solid crystal region 110. On the horizontal dotted line.

In FIG. 5B, the strip-shaped insulating portion 112 is composed of two straight portions and an arc portion between the two straight portions and is located between the positive electrode pad 13 and the negative electrode pad 15, and the two LED chips 20 are, for example, the specification model number 2240. The LED chips are symmetrically disposed in the cup-shaped solid crystal region 110 and are connected to the positive electrode pad 13 and the negative electrode pad 15 and are fixed on the negative electrode pad 15. The two LED chips 20 are arranged in a longitudinal direction and are opposite to the cup cup. The geometrical center of the solid crystal region 110 (the intersection of the horizontal dashed line and the longitudinal dashed line in FIG. 5B) is symmetrically distributed with respect to the transverse dashed line, and the geometric center of each LED wafer 20 is located substantially at the geometric center of the cup-shaped solid crystal region 110. Vertically on the dotted line.

In FIG. 5C, the strip-shaped insulating portion 112 is composed of two straight portions and an arc portion between the two straight portions and is located between the positive electrode pad 13 and the negative electrode pad 15, and one LED chip 20 is, for example, a model number 2240. The LED chips are symmetrically disposed in the cup-shaped solid crystal region 110 and are connected to the positive electrode pad 13 and the negative electrode pad 15 and are fixed on the negative electrode pad 15. The specific geometric center of the single LED chip 20 is substantially cup-shaped and solid-shaped. The geometric center of the region 110 (the intersection of the horizontal dashed line and the longitudinal dashed line in Fig. 5C) coincides with the length direction of the lateral direction shown in Fig. 5C.

In FIG. 5D, the strip-shaped insulating portion 112 is composed of two straight portions and an arc portion between the two straight portions and is located between the positive electrode pad 13 and the negative electrode pad 15, and one LED chip 20 is, for example, a model number 2240. The LED chips are symmetrically disposed in the cup-shaped solid crystal region 110 and are connected to the positive electrode pad 13 and the negative electrode pad 15 and are fixed on the negative electrode pad 15. The specific geometric center of the single LED chip 20 is substantially cup-shaped and solid-shaped. The geometric center of the region 110 (the intersection of the horizontal dashed line and the longitudinal dashed line in Fig. 5D) coincides with the longitudinal direction thereof as shown in the longitudinal direction shown in Fig. 5D.

In FIG. 5E, the strip-shaped insulating portion 112 is composed of two straight portions and an arc portion between the two straight portions and is located between the positive electrode pad 13 and the negative electrode pad 15, and the two LED chips 20 are, for example, the specification model F2630. The LED chips are symmetrically disposed in the cup-shaped solid crystal region 110 and are connected to the positive electrode pad 13 and the negative electrode pad 15 and are fixed on the negative electrode pad 15. The two LED chips 20 are arranged in a longitudinal direction and are opposite to the cup cup. The geometrical center of the solid crystal region 110 (the intersection of the horizontal dashed line and the longitudinal dashed line in FIG. 5B) is symmetrically distributed with respect to the transverse dashed line, and the geometric center of each LED wafer 20 is located substantially at the geometric center of the cup-shaped solid crystal region 110. Vertically on the dotted line. Further, a positive electrode pad 30 for antistatic electrodes is soldered and fixed to the positive electrode pad 13, and a positive electrode of the polar nano diode wafer 30 is connected to the negative electrode pad 15.

Referring to FIG. 6, in another embodiment of the present invention, the strip-shaped insulating portion 112 between the positive electrode pad 13 and the negative electrode pad 15 to open the positive electrode pad 13 and the negative electrode pad 15 is also designed to have two bends, but It may be composed of three straight segments such that it is generally U-shaped.

Referring to FIG. 7, in another embodiment, the strip-shaped insulating portion 112 between the positive electrode pad 13 and the negative electrode pad 15 to space the positive electrode pad 13 and the negative electrode pad 15 may even be designed to have a bend, and for example It consists of two straight segments, making it roughly L-shaped.

Finally, an embodiment of the present invention further provides an LED package structure including the LED holder 10 in any one of the foregoing embodiments, and one or more LED chips 20 centered symmetrically in the cup-shaped solid crystal region 10 of the LED holder 10. And a package (not shown) that is filled in the cup-shaped solid crystal region 10 and covers each of the LED chips 20. Each of the LED chips 20 is fixed on the negative electrode pad 15 and electrically connected to the positive electrode pad 13 and the negative electrode pad 15 by a wire bonding method, for example, a fluorescent rubber image mixed with a fluorescent powder or a fluorescent powder coating. Layer of silicone and so on.

In summary, in the embodiment of the present invention, the structure of the electrode pads (positive pad, negative pad) on the LED bracket is such that one of the electrode pads, such as the positive pad, is of sufficient size to be soldered or placed with a pole. The nano-diode wafer can be used, so that the other electrode pad is as large as possible, so that the LED chip can be symmetrically disposed on the LED bracket, thereby achieving the purpose of increasing the luminous efficiency and heat dissipation effect of the wafer. In addition, it can be understood that the strip-shaped insulating portion between the positive electrode pad and the negative electrode pad to space the positive electrode pad and the negative electrode pad is not limited to have one or two bends as described above, which may have more bends In addition, the model of the LED chip is not limited to the aforementioned models, and may be other models; and the number of LED chips that are symmetrically disposed on the LED bracket is not limited to one or two of the foregoing, and may also be More.

In the above, in the present invention, the present invention has been disclosed in the above embodiments, and is not intended to limit the present invention, and it is within the spirit and scope of the present invention. The scope of protection of the present invention is defined by the scope of the appended claims.

10‧‧‧LED bracket

20‧‧‧LED chip

11‧‧‧Insert substrate

110‧‧‧ Bowl cup-shaped solid crystal area

112‧‧‧ Strip insulation

13‧‧‧ positive pad

15‧‧‧Negative pad

W‧‧‧Width

122‧‧‧The junction of the positive electrode pad and the insulating substrate

124‧‧‧The junction of the negative electrode pad and the insulating substrate

30‧‧‧Dano diode wafer

FIG. 1 is a schematic perspective structural view of an LED holder (with an LED chip) according to an embodiment of the present invention. 2 is a schematic exploded perspective view of the structure shown in FIG. 1. Figure 3 is a plan view showing the structure of Figure 1. Fig. 4A is a cross-sectional view taken along line IVA-IVA of Fig. 3. Fig. 4B is a cross-sectional view taken along line IVB-IVB of Fig. 3. 5A-5E illustrate various examples of application of an LED bracket to an LED chip package according to an embodiment of the present invention. FIG. 6 is a schematic plan view showing the structure of an LED holder (with an LED chip) according to another embodiment of the present invention. FIG. 7 is a schematic plan view showing another structure of an LED holder (with an LED chip) according to another embodiment of the present invention.

Claims (10)

An LED holder comprising: an insulating substrate, a first electrode pad and a second electrode pad; wherein the insulating substrate is formed with a cup-shaped solid crystal region and strip insulation in the cup-shaped solid crystal region The first electrode pad and the second electrode pad are fixed on the insulating substrate and are spaced apart from the bottom of the cup-shaped solid crystal region by the strip-shaped insulating portion, the strip insulation a portion having at least one bend in the cup-shaped die-bonding region, the strip-shaped insulating portion filling a region between the first electrode pad and the second electrode pad, and the first electrode pad and The second electrode pads respectively abut the opposite sides of the strip-shaped insulating portion, and a shape of a side of the first electrode pad adjacent to the strip-shaped insulating portion is adjacent to the strip of the second electrode pad The shape of one side of the insulating portion is complementary to the concavities and convexities in the cup-shaped solid crystal region of the bowl. The LED holder according to claim 1, wherein the strip-shaped insulating portion has a plurality of the bent portions in the cup-shaped solid crystal region. The LED holder of claim 2, wherein the strip-shaped insulating portion includes two straight segments and an arc connected between the two straight segments in the cup-shaped solid crystal region a first electrode pad having a concave curved portion on a side of the bowl-shaped solid crystal region adjacent to the strip-shaped insulating portion, and the second electrode pad is cup-shaped in the bowl The side adjacent to the strip-shaped insulating portion in the region correspondingly has a convex arc-shaped portion. The LED holder according to claim 2, wherein the strip-shaped insulating portion is formed of three straight segments connected in series in the cup-shaped solid crystal region and is substantially U-shaped. The LED holder of claim 1, wherein the strip-shaped insulating portion is formed by two connected straight segments in the cup-shaped solid crystal region and has a bent portion, thereby substantially L type. The LED holder of claim 1, wherein an area ratio of the first electrode pad and the second electrode pad in the cup-shaped solid crystal region is 1:3 to 1:5. The LED holder of claim 1, wherein the width of the first electrode pad in the cup-shaped solid crystal region of the bowl is 0.15 mm to 0.3 mm. The LED holder of claim 1, wherein the junction of the first electrode pad and the insulating substrate and the junction of the second electrode pad and the insulating substrate are stepped. An LED package structure comprising: at least one LED chip, a package body, and the LED holder according to claim 1; wherein the at least one LED chip is centrally symmetrically distributed in the cup-shaped solid crystal of the LED holder Connected to the first electrode pad and the second electrode pad in a region and fixed on the second electrode pad; the package is filled in the cup-shaped solid crystal region and covers the at least one LED Wafer. The LED package structure of claim 9, further comprising a polar nanodiode wafer soldered to the first electrode pad and connected to the second electrode pad.