JP2012221962A - Led package and substrate for the led package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED package which inhibits molding defects, such as the occurence of resin non filling regions and voids, between die pads of a lead frame and improves the resin molding property.SOLUTION: An LED package is formed by cutting a lead frame 10 on which multiple LED chips are mounted and has at least one LED chip. The LED package includes: clearance parts 14, each of which is provided between a base side lead 10a and a terminal side lead 10b which form the lead frame 10; and a resin 20 formed on the lead frame 10 so as to enclose the LED chips and the interior of each clearance part 14 to form the package. Each clearance part 14 is inclined relative to a side surface of the package.

Description

  The present invention relates to an LED package with improved resin moldability and an LED package substrate.

  Conventionally, as disclosed in Patent Document 1, there is an LED package including an LED chip that emits light of a predetermined wavelength. Such an LED package is manufactured by mounting a plurality of LED chips on a lead frame to form an LED package substrate, and cutting the LED package substrate into individual pieces.

  In Patent Document 1, a reflector formed by a primary molding resin (white resin) by transfer molding is provided so as to surround each of a plurality of LED chips on a lead frame. The plurality of LED chips are sealed with a secondary molding resin (transparent resin) having a function as a lens portion.

JP 2010-182770 A

  In the LED package disclosed in Patent Document 1, when a reflector (resin) is formed by transfer molding, the resin forms the reflector while flowing (moving) in a predetermined direction inside the cavity of the mold. At this time, since the gap (clearance portion) between the die pads of the lead frame constituting the LED package (LED package substrate) is narrow, the resin moldability (resin filling property) between the die pads is poor. Further, in the conventional LED package, the mounting function is given priority in order to secure the mounting area of the semiconductor chip and the installation area of the wire, and the resin moldability is not considered.

  Therefore, the present invention provides an LED package and an LED package substrate that are improved in resin moldability by suppressing molding defects such as resin unfilled regions between the die pads of the lead frame and generation of voids.

  An LED package according to an aspect of the present invention is an LED package having at least one LED chip formed by cutting a lead frame on which a plurality of LED chips are mounted, and includes a first frame constituting the lead frame. A clearance portion provided between the lead portion and the second lead portion; and a resin which is molded on the lead frame and inside the clearance portion so as to surround the LED chip and constitutes a package. The clearance portion is inclined with respect to the side surface of the package.

  An LED package according to another aspect of the present invention is an LED package having at least one LED chip formed by cutting a lead frame on which a plurality of LED chips are mounted. A clearance portion provided between the lead portion and the second lead portion, and a resin which is molded on the lead frame and inside the clearance portion so as to surround the LED chip and constitutes a package. And the first width of the clearance portion on the first side surface side of the package is wider than the second width of the clearance portion on the second side surface side facing the first side surface.

  An LED package substrate according to another aspect of the present invention is provided between a lead frame having a first lead portion and a second lead portion, and the first lead portion and the second lead portion. A clearance portion and a resin formed on the lead frame and inside the clearance portion to form a package, and the clearance portion is formed on a side surface of the package obtained by cutting the lead frame. It is inclined with respect to it.

  An LED package substrate according to another aspect of the present invention is provided between a lead frame having a first lead portion and a second lead portion, and the first lead portion and the second lead portion. A clearance portion and a resin which is molded on the lead frame and inside the clearance portion to form a package, and the first width of the clearance portion on the resin molding gate side is the gate Wider than the second width of the clearance portion on the opposite side.

  Other objects and features of the present invention are illustrated in the following examples.

  According to the present invention, it is possible to provide an LED package and an LED package substrate with improved resin moldability by suppressing molding defects such as resin unfilled regions between the die pads of the lead frame and generation of voids.

3 is a configuration diagram of a lead frame in Embodiment 1. FIG. 1 is a configuration diagram of an LED package substrate in Example 1. FIG. 7 is a modification of the lead frame in Embodiment 1. 7 is a modification of the lead frame in Embodiment 1. 6 is a configuration diagram of a lead frame in Embodiment 2. FIG. 6 is a configuration diagram of an LED package substrate in Example 2. FIG. 10 is a modification of the lead frame in Embodiment 2.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same members are denoted by the same reference numerals, and redundant description is omitted.

  First, an LED package and an LED package substrate in Example 1 of the present invention will be described. The LED package of the present embodiment is formed by cutting a lead frame on which a plurality of LED chips are mounted, and has at least one LED chip. FIG. 1 is a configuration diagram of a lead frame in this embodiment, FIG. 1 (a) is a plan view of the lead frame, FIG. 1 (b) is a plan view showing a state in which the lead frame is clamped with a mold, and FIG. (C) shows each sectional drawing cut | disconnected by line CC in FIG.1 (b).

  The lead frame 10 of the present embodiment is configured in a planar shape by forming a plating layer on the surface of a material such as a copper alloy or an iron alloy. A plurality of LED chips (not shown) are mounted on the lead frame 10 after sealing the resin for the reflector, and after passing through a dicing (dividing) process for cutting the lead frame 10 after sealing the resin for the lens. A plurality of LED packages as final products are completed. A region 150 indicated by a broken line in FIG. 1A corresponds to the outer shape of one LED package. Such a resin for a reflector and a lens is molded by a MAP (Mold Array Process) method. In these moldings, a plurality of gates are arranged with respect to one side of the cavity in order to collectively fill the cavity including the plurality of LED package regions with the resin.

  As shown in FIG. 1A, in this embodiment, the lead frame 10 includes a base side lead 10a (first lead portion) and a terminal side lead 10b (second lead portion) that function as a die pad. It is configured. An LED chip (not shown) is mounted on the base side lead 10a. An LED chip is a semiconductor element that includes a pair of electrodes, an anode electrode (positive electrode) and a cathode electrode (negative electrode), and emits light by applying a predetermined voltage with a forward bias between these electrodes.

  The base-side lead 10a and the terminal-side lead 10b are separated from each other by a clearance portion 14 (gap between die pads), and are electrically connected to each electrode of the LED chip by wire bonding using gold wire, flip chip, or the like. Is done. As described above, the clearance portion 14 is provided between the base-side lead 10a and the terminal-side lead 10b constituting the lead frame 10. In this embodiment, the base-side lead 10a is connected to the cathode electrode and the terminal-side lead 10b is connected to the anode electrode. However, the present invention is not limited to this. Further, the LED chip may be mounted on the terminal side lead 10b, or may be mounted on both leads.

  The lead frame 10 is formed with a half-etching 12 (concave groove) whose thickness is reduced by, for example, chemical treatment at a cutting site when the lead frame 10 is separated into a plurality of LED packages. Note that press working may be used to reduce the thickness of the lead frame 10 in this way. By forming the half etching 12 at the cutting portion of the lead frame 10, it is easy to cut when dividing into a plurality of LED packages.

  In the lead frame 10, the clearance portion 14 is configured to be inclined by an angle α with respect to the side of the region 150 showing the outer shape of the LED package (the right side or the left side in FIG. 1A). That is, the clearance portion 14 is inclined with respect to the side surface of a package obtained by cutting the lead frame 10 (an LED package as a final product after cutting). The clearance portion 14 is formed on a pair of sides (upper side and lower side in FIG. 1B) that are not the gate side side (left side of FIG. 1B) and the opposite side (right side of FIG. 1B). It is formed over.

As shown in FIG. 1B, when the lead frame 10 is clamped with a mold, the resin flows in the directions of arrows A _{1 to} A ₃ from a plurality of gates located on the left end side of the figure. The plurality of gates are provided, for example, in the same number as the number of forming rows of the LED package, and are arranged on a line (corresponding to a one-dot chain line in FIG. 1B) through which the centers of the plurality of packages arranged in the column direction pass. ing. At this time, as shown in FIG. 1C, the lead frame 10 is clamped by a mold including an upper mold 50 and a lower mold 60. The upper mold 50 includes a convex portion 55 and a cavity 16. As shown by the two-dot chain line in FIG. 1B in plan view, the side surface of the convex portion 55 is inclined, and the end surface (tip portion) contacts the surface of the lead frame 10. The cavity 16 is disposed on one surface side (the upper surface side in FIG. 1C) of the lead frame 10, and a resin described later is formed by the resin flowing into the space on the lead frame 10.

In the lead frame 10 of this embodiment, since the clearance portion 14 is inclined by an angle alpha, for example, with respect to the upper left of the clearance portion 14, the resin flowing in the direction of the arrow A ₁ is the direction of the arrow B ₁ (clearance portion 14). That is prevented from resin flowing in the direction of arrow A ₂ is introduced into the upper left of the clearance portion 14. Similarly, with respect to the center left of the clearance portion, tends to flow the resin flows in the direction of arrow A _2, the resin flows in the direction of arrow A ₃ is hardly flows. Resin flowing in the direction of arrow A ₃ is, and is easy to flow into the lower left of the clearance portion, preferentially flow into the lower left clearance sector. The same applies to other clearance portions.

  Thus, by inclining the clearance portion 14 by the angle α, the resin flowing from the gate can be preferentially flowed into the clearance portion 14 from one direction. For this reason, according to the configuration of the present embodiment, compared with the conventional case where the clearance portion is not inclined, a region (resin unfilled region) in which the resin is not filled in the clearance portion is generated, and voids are generated. Can be effectively suppressed.

  Next, the configuration of the LED package substrate obtained by filling the lead frame 10 with resin will be described. In this embodiment, the LED package substrate refers to a state before resin is molded on the lead frame and the LED chip is not mounted on the lead frame. FIG. 2 is a configuration diagram of an LED package substrate in this embodiment, FIG. 2 (a) is a plan view of the LED package substrate, and FIG. 2 (b) is a line BB in FIG. 2 (a). Sectional views when cut are shown.

  As shown in FIGS. 2A and 2B, a resin 20 is formed in a predetermined region (half etching 12, clearance portion 14, and reflector 22) on the lead frame 10. In this embodiment, the resin 20 is molded on the lead frame 10 and inside the clearance portion 14 and the half-etching 12 so as to surround the LED chip to constitute a package.

  The resin 20 is a white resin, for example, a thermosetting resin made of a silicone resin or an epoxy resin containing white powder such as titanium oxide or alumina and silica. The resin 20 is clamped from both sides of the lead frame 10 using the upper die 50 and the lower die 60 (die), and is poured into the resin by transfer molding to be cured. Are integrally formed. As described above, the LED package substrate according to the present embodiment has a map structure that is molded together with the resin 20. However, the present invention is not limited to this, and can be applied to an LED package substrate having a matrix structure.

  The resin 20 functions as a reflector 22 (side wall 22a) that reflects light emitted from an LED chip (not shown) upward (FIG. 2B). The resin 20 also has a function of improving the strength of the LED package. The resin 20 is not formed on the lead frame 10 where the LED chip is mounted in a plurality of regions by being clamped by the convex portion 55. These areas serve as LED chip mounting areas 30 (recesses) for mounting the LED chips. In the LED chip mounting region 30, the clearance portion 14 is inclined by an angle α with respect to the direction of the left side and the right side of the region 150, and the clearance portion 14 is filled with the resin 20. Thus, in the clearance part 14, the area | region (resin non-filling area | region) and the void which are not filled with resin 20 have not generate | occur | produced.

  As shown in FIG. 2A, the resin 20 as the reflector 22 is formed in an annular shape on the lead frame 10 so as to surround the LED chip mounting region 30. Further, as shown in FIG. 2B, the resin 20 as the reflector 22 has a mortar in which the diameter of the LED chip mounting region 30 increases (the side wall 22a is inclined) as the distance from the lead frame 10 increases. It has a shape. By having such a shape, the resin 20 as the reflector 22 can efficiently reflect the light emitted from the LED chip upward.

  Next, a modification of the lead frame in the present embodiment will be described. FIG. 3 shows a modification of the lead frame in this embodiment. FIG. 3 (a) is a plan view of the lead frame when the width of the clearance portion is changed, and FIG. 3 (b) is a view in FIG. 3 (a). FIG. 3C is a plan view of the lead frame when the half-etching width is changed, and FIG. 3D is a line DD in FIG. 3C. Sectional views cut along with are shown respectively.

As shown in FIGS. 3A and 3B, the first modification is a lead frame when the width of the clearance portion is changed. The clearance portion 14a is formed between the base side lead 10c and the terminal side lead 10d. The clearance portion 14a is provided with an angle α as in the case of the clearance portion 14, but in addition to this, the width Wa on the upper side (first position closer to the gate) in FIG. ₁ (first width) is configured to be wider than width Wa ₂ (second width) on the lower side (second position on the side far from the gate). That is, the width Wa ₁ on the side where the resin flows in from the gate is made wider than the width Wa ₁ on the side where the resin flows out (the side on which the resin hardly flows). For this reason, the resin from the gate more easily flows into the clearance portion 14a from a specific direction (the upper side in FIG. 3B). In other words, it can be made more difficult for the resin to flow into the clearance portion 14a from the end that is formed far and narrow from the gate. Therefore, in the clearance part 14a, generation | occurrence | production of the resin unfilled area | region and a void can be suppressed more effectively.

  As shown in FIGS. 3C and 3D, the second modification is a lead frame when the half etching width in the clearance portion is changed. The clearance portion 14b is formed between the base side lead 10e and the terminal side lead 10f. Half etching 15 is formed at the end of the base side lead 10e and the terminal side lead 10f on the side where the clearance 14b is provided.

In this modified example, the clearance portion 14 b is provided to be inclined by an angle α as with the clearance portion 14. In addition, the width of the clearance portion 14b is constant on the surface side (LED chip mounting side) of the lead frame, but the width of the half etching 15 is changed. Specifically, the first width on the side close to the gate of the half etching 15 is wider than the second width on the side far from the gate. For this reason, the width Wb ₁ on the upper side (side closer to the gate) in FIG. 3D is on the lower side (side far from the gate) on the back side of the lead frame (the side opposite to the LED chip mounting surface). It is configured to be wider than the width Wb _2. That is, the width Wb ₁ on the side where the resin flows in from the gate is made wider than the width Wb ₁ on the side where the resin flows out (the side on which the resin hardly flows). For this reason, the resin from the gate more easily flows into the clearance portion 14b from a specific direction (upper side in FIG. 3D). Therefore, in the clearance part 14b, generation | occurrence | production of the resin unfilled area | region and a void can be suppressed more effectively.

Moreover, in the clearance part 14b, only the part of the back surface half-etched can also be inclined. Further, only the width of the half-etched back surface side can be set such that the width Wb ₁ on the side where the resin flows in from the gate is wider than the width Wb ₁ on the side where the resin flows out (the side on which the resin hardly flows). Further, when the terminal-side lead 10d is arranged as shown in FIG. 3, only the half-etching width on the back surface of the terminal-side lead 10d is changed, and the base-side lead 10c is clamped on the entire surface without being half-etched. It is also possible to preferentially flow in from one direction. In these cases, since the shape of the LED chip mounting region is the same as that of a normal lead frame, the degree of freedom of arrangement of the LED chips is high and preferable.

FIG. 4 shows still another modified example (third modified example) of the lead frame in this embodiment. FIG. 4A is a sectional view of the lead frame, and FIG. 4B is a plan view thereof. Show. FIG. 4A is a cross-sectional view taken along line AA in FIG. The third modification is the same as the configuration of the above-described embodiment in that the clearance portion is inclined at an angle α, but it is formed at the cutting site when cutting into the LED package as the final product. The half etching 12a is different from the above-described embodiment in that the position of the half-etching 12a is displaced toward the lower side of the figure (the end of the clearance portion on the side where the resin is preferentially introduced). That is, as shown in FIG. 3 (b), the distance L ₁ from the lower end of the upper terminal-side lead 10b up to the half etching 12a from the upper end of the lower terminal side lead 10b up to the half etching 12a greater than the distance _{L 2.} Thus, the half etching 12a is formed between the adjacent terminal side leads 10b, and this half etching 12a is formed close to one of the adjacent terminal side leads 10b.

  For this reason, the resin from the gate more easily flows into the clearance portion 14 from a specific direction (the direction of arrow D in FIG. 4B). Therefore, even by adopting such a configuration, it is possible to effectively suppress the resin unfilled region and the generation of voids in the clearance portion 14. Such a configuration is particularly effective when forming an LED package substrate using a mold having no cavity 16 so as to fill the space between the leads without forming a reflector.

  Next, an LED package and an LED package substrate in Example 2 of the present invention will be described. FIG. 5 is a configuration diagram of the lead frame in the present embodiment, FIG. 5A is a plan view of the lead frame, and FIG. 5B is a plan view showing a state in which the lead frame is clamped with a mold. .

  As shown in FIGS. 5A and 5B, the lead frame 100 according to the present embodiment includes a base-side lead 100a and a terminal-side lead 100b. A wide clearance portion 140a and a narrow clearance portion 140b are provided between the base side lead 100a and the terminal side lead 100b. In addition, a half-etching 120 is formed at a cutting portion of the lead frame 100 when the LED packages are separated into individual pieces.

As shown in FIG. 5B, when the lead frame 10 is clamped with a mold, the resin flows in the direction of arrow A from a plurality of gates located at the left end. The wide clearance portion 140a has a width Wc ₁ (first width), and the narrow clearance portion 140b has a width Wc ₂ (second width). Width Wc ₁ clearance portion 140a is configured to be wider than the width Wc ₂ clearance portion 140b. In the LED package substrate of the present embodiment thus, the gate side of the resin molded width Wc ₁ clearance portion 140a of the (left side in FIG. 5 (b)), the clearance portion in the gate and the opposite side (the right side) 140a wider than the width Wc ₂ of. For this reason, in the LED package separated by cutting the LED package substrate, the width of the clearance portion on the first side surface (left side) of the package is the second side surface facing the first side surface. It is wider than the width of the clearance part on the side (right side).

For this reason, a part of the resin flowing from the gate in the direction of arrow A proceeds in the direction of arrow B and flows into the center clearance portion 140a. The width Wc ₂ of the center left of the clearance portion 140b is narrower than the width Wc ₁ clearance portion 140a, the resin flowing in the direction of arrow A, hardly flows in the direction of the arrow C, the center left of the clearance portion Inflow into the inside of 140b is suppressed. Therefore, by changing the width of the clearance portion in the adjacent LED chip mounting region, it is possible to effectively suppress the occurrence of a resin unfilled region or void in the clearance portion 14. Even in an individualized LED package, the gate arrangement (resin flow direction) with respect to the clearance portion can be determined by observing the internal structure of the package.

  Next, the configuration of the LED package substrate obtained by filling the lead frame 100 with resin will be described. FIG. 6 is a configuration diagram (plan view) of the LED package substrate in the present embodiment. As shown in FIG. 6, resin 20 is formed in predetermined regions (half etching 120, clearance portions 140 a and 140 b, and reflector 220) on lead frame 100. Although the LED package substrate of the present embodiment has a map structure that is molded together with the resin 20, it is also applicable to a matrix structure LED package substrate.

The resin 20 functions as a reflector 220 (side wall 220a) that reflects light emitted from an LED chip (not shown), as in the first embodiment. Further, the resin 20 is not formed in a plurality of regions on the lead frame 100 where the LED chip is to be mounted, and these regions become the LED chip mounting region 300. Inside the LED chip mounting area 309, the width Wc ₁ clearance portion 140a is wider than the width Wc ₂ clearance portion 140b, the clearance portion 140a, the inside of 140b resin 20 is filled. As described above, since the resin 20 can be flowed only from a predetermined direction, the resin unfilled region and voids are not generated in the clearance portions 140a and 140b.

  Similar to the first embodiment, the resin 20 as the reflector 220 is formed in an annular shape on the lead frame 100 so as to surround the LED chip mounting region 300. Further, the resin 20 as the reflector 220 has a mortar shape in which the diameter of the LED chip mounting region 300 becomes larger (as the side wall 220a is inclined) as the distance from the lead frame 100 increases.

Next, a modification of the lead frame in the present embodiment will be described. FIG. 7 shows a modification of the lead frame in the present embodiment. Lead frame 110 is similar to the configuration described above, includes a clearance portion 140b having a clearance portion 140a and the width Wc ₂ has a width Wc _1, also configured with a half etching 120. Instead of the half-etching 120, the cutting portion disposed between the adjacent base-side leads 100a of the lead frame 110 and between the adjacent terminal-side leads 100b is inclined by an angle β in the resin flow direction instead of the half etching 120. Half etching 120a is formed. That is, in the lead frame 110, the half etching 120a is inclined with respect to the side surface of the package.

By forming the half etching 120a inclined in this way, the resin can easily flow into the clearance portion 140a from the directions of the arrows B ₁ and B ₂ . Therefore, it is possible to more effectively suppress the resin unfilled region and the generation of voids in the clearance portions 140a and 140b. Such a configuration is particularly effective when forming an LED package substrate using a mold having no cavity 16 so as to fill the space between the leads without forming a reflector.

  According to each of the above embodiments, an LED package and an LED package substrate with improved resin moldability are provided by suppressing molding defects such as resin unfilled areas and voids in the clearance portion (between die pads) of the lead frame. can do.

  The embodiment of the present invention has been specifically described above. However, the present invention is not limited to the matters described as the above-described embodiments, and can be appropriately changed without departing from the technical idea of the present invention.

10, 100, 110 Lead frame 10a, 10c, 10e, 100a Base side lead 10b, 10d, 10f, 100b Terminal side lead 12, 15, 120, 120a Half etching 14, 14a, 14b, 140a, 140b Clearance section 16 Cavity 20 Resin 30, 300 LED chip mounting area 22, 220 Reflector 50 Upper mold 55 Projection 60 Lower mold

Claims (11)

An LED package formed by cutting a lead frame on which a plurality of LED chips are mounted and having at least one LED chip,
A clearance portion provided between a first lead portion and a second lead portion constituting the lead frame;
A resin which is molded on the lead frame so as to surround the LED chip and inside the clearance part to constitute a package;
The LED package, wherein the clearance portion is inclined with respect to a side surface of the package.   2. The LED package according to claim 1, wherein the first width of the clearance portion at the first position is wider than the second width at the second position. Half etching is formed at the end of the first lead portion and the second lead portion on the side where the clearance portion is provided,
2. The LED package according to claim 1, wherein a first width at the first position of the half etching is wider than a second width at the second position.   3. The LED package according to claim 1, wherein the lead frame is formed with half etching inclined with respect to a side surface of the package. An LED package formed by cutting a lead frame on which a plurality of LED chips are mounted and having at least one LED chip,
A clearance portion provided between a first lead portion and a second lead portion constituting the lead frame;
A resin which is molded on the lead frame so as to surround the LED chip and inside the clearance part to constitute a package;
The first width of the clearance portion on the first side surface side of the package is wider than the second width of the clearance portion on the second side surface facing the first side surface. package. A lead frame having a first lead portion and a second lead portion;
A clearance portion provided between the first lead portion and the second lead portion;
A resin that is molded on the lead frame and inside the clearance portion to form a package;
The LED package substrate, wherein the clearance portion is inclined with respect to a side surface of the package obtained by cutting the lead frame.   The LED package substrate according to claim 6, wherein the first width of the clearance portion at the first position is wider than the second width at the second position. Half etching is formed at the end of the first lead portion and the second lead portion on the side where the clearance portion is provided,
The LED package substrate according to claim 6, wherein the first width at the first position of the half etching is wider than the second width at the second position. Half etching is formed between the adjacent second lead portions,
9. The LED package substrate according to claim 6, wherein the half etching is formed adjacent to one of the adjacent second lead portions. 10.   8. The LED package substrate according to claim 6, wherein the lead frame is formed so that half etching is inclined with respect to a side surface of the package. 9. A lead frame having a first lead portion and a second lead portion;
A clearance portion provided between the first lead portion and the second lead portion;
A resin that is molded on the lead frame and inside the clearance portion to form a package;
A substrate for an LED package, wherein a first width of the clearance portion on the resin molding gate side is wider than a second width of the clearance portion on the opposite side to the gate.