JP2012253234A - Lead frame substrate for led element, and light emission element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent sags at a cutting-end of a tie bar occurring when being cut in a lead frame substrate for an LED element.SOLUTION: The lead frame substrate for an LED element includes a lead frame 1 in which a plurality of sets of an LED chip mounting section 2 having a pad for mounting the LED chips and an electrically connecting area 3 which is arranged apart from the LED chip mounting section 2 and forms a lead to be electrically connected to the LED chip are connected through the tie bars 60, 70 and 80; and a resin covering the lead frame 1 except the LED chip mounting section 2 and a part of the electrically connecting area 3. In the lead frame substrate for an LED element, the resin together with the tie bars 60, 70, and 80 are cut to produce individual piece substrates. The tie bars 60, 70, and 80 are extended longer than a cutting margin, while the outer periphery are surrounded by the resin.

Description

  The present invention relates to a lead frame substrate for an LED (Light Emitting Diode) element and a light emitting element.

In general, a lead frame on which an LED element is mounted is a metal sheet for a lead frame made of an alloy thin plate such as iron-nickel or an alloy thin plate such as copper-nickel-tin. This is manufactured by photoetching using an etchant. In addition, the lead frame includes an LED chip mounting portion having a pad (island portion) for mounting the LED chip, and an inner portion electrically spaced from the LED chip mounting portion and electrically connected to the LED chip mounting portion. An electrical connection area having a lead and an outer lead is provided (see Patent Documents 1 to 3).
The lead frame pad has a mounting portion (mounting surface) for mounting the LED element on the front surface side, and driving heat generated from the LED chip and heat due to environmental conditions around the LED chip on the rear surface side. A heat dissipating part (heat dissipating plate) for dissipating is provided, and heat is released from the heat dissipating part on the back side of the pad to the outside so that heat is not accumulated in the LED chip.

  Such a lead frame (unit lead frame) is formed by, for example, etching a metal plate material to form a lead frame in which a plurality of lead frame patterns are connected by a connecting portion called a tie bar, and then performing resin molding. The LED element lead frame substrate is formed, and the LED element lead frame substrate is cut into individual pieces along the cutting margin through which the tie bar penetrates in any step before and after the LED element wiring step. Manufactured.

JP 2003-8071 A JP 2003-347600 A JP 2004-172160 A

However, the conventional lead frame substrate for LED element and the light emitting element as described above have the following problems.
In the prior art, when the lead frame substrate for an LED element is cut into pieces, sagging has occurred at the cut end of the tie bar made of a ductile material. Such sagging not only results in the shape error of the individual light emitting elements, but also the cause of the occurrence of abnormalities and defects such as short circuits in the subsequent assembly process due to peeling of the sagging part and generation of metal foreign matter. There is a problem of becoming.

The present invention has been made in view of the above problems, and provides a lead frame substrate for an LED element that can prevent a tie bar cut from occurring when the lead frame substrate for an LED element is cut. With the goal.
It is another object of the present invention to provide a light emitting element that can prevent defects caused by sagging of tie bars by forming a light emitting element using such a lead frame substrate for an LED element.

  In order to solve the above-described problems, in the invention according to claim 1, an LED chip mounting portion having a pad on which the LED chip is mounted, and an LED chip mounting portion spaced apart from the LED chip mounting portion and electrically connected to the LED chip. A plurality of electrical connection area portions that form leads connected to the lead frame, and a portion of the lead frame excluding the LED chip mounting portion and a part of the electrical connection area portion. A lead frame substrate for an LED element for manufacturing an individual substrate by cutting the tie bar together with the resin portion, wherein the tie bar extends longer than a cutting allowance, and the resin portion And the tie bar is formed so that its width gradually becomes narrower at a portion close to the outer surface of the resin portion. And it formed.

  According to a second aspect of the present invention, in the lead frame substrate for an LED element according to the first aspect, the tie bar is formed by half etching.

  According to a third aspect of the present invention, in the light emitting element, an LED chip is mounted on the individual substrate manufactured by cutting the tie bar of the lead frame substrate for the LED element according to the first or second aspect. To do.

According to the lead frame substrate for an LED element of the present invention, since the tie bar is formed surrounded by the resin portion, deformation of the tie bar is restricted by the resin portion when the tie bar is cut. There is an effect that it is possible to prevent sagging of the tie bar which sometimes occurs.
Furthermore, since the tie bar is formed up to a portion close to the outer surface of the resin portion while being gradually narrowed, the strength can be increased, thereby maintaining the strength of the lead frame substrate for the LED element. There is also.
Since the light emitting device of the present invention uses the lead frame substrate for an LED device of the present invention, there is an effect that it is possible to prevent defects due to sagging of tie bars.

BRIEF DESCRIPTION OF THE DRAWINGS It is typical (a) top view which shows the structure of the light emitting element of embodiment of this invention, (b) Right view, (c) Side view of D view. It is a typical back view which shows the structure of the light emitting element of embodiment of this invention. It is AA sectional drawing in FIG. It is BB sectional drawing in FIG. It is a top view which shows the lead frame board | substrate for LED elements of embodiment of this invention. It is the (a) top view and (b) back view of the lead frame used for the lead frame substrate for LED elements of embodiment of this invention. It is a process flow figure of a manufacturing process of a lead frame substrate for LED elements and a light emitting element of an embodiment of the present invention. (A) The schematic diagram which shows the mode of the cutting process of the lead frame substrate for LED elements of embodiment of this invention, (b) The schematic diagram which shows an example of the cut surface after a cutting | disconnection. (A) Schematic diagram showing the state of the cutting process of the prior art, (b) Schematic diagram showing an example of the cut after cutting, (c) EE sectional view, (d) Other examples of the cut after cutting It is the schematic diagram to show, and (e) The FF sectional drawing.

Hereinafter, a lead frame substrate for an LED element and a light emitting element according to an embodiment of the present invention will be described with reference to the accompanying drawings.
1A and 1B are a schematic plan view and a right side view showing a configuration of a light emitting device according to an embodiment of the present invention. FIG.1 (c) is a side view of the D view in Fig.1 (a). FIG. 2 is a schematic back view showing the configuration of the light emitting device of the embodiment of the present invention. FIG. 3 is a cross-sectional view taken along line AA in FIG. 4 is a cross-sectional view taken along the line BB in FIG.

As shown in FIGS. 1A, 1B, 1C, and FIGS. 2 to 4, the schematic configuration of the light emitting device 50 of the present embodiment is such that the outer shape is formed in a rectangular parallelepiped shape. A lead frame 1A (see FIG. 1 (a)) formed by etching an alloy plate (thickness t0) of nickel-tin or the like into a predetermined shape by etching, and an LED element The LED chip 10, the separated lead frame 1 A and the resin package 4 (resin part) for packaging the LED chip 10, and the transparent resin part 9 for sealing the LED chip 10 so as to transmit light are provided.
Here, the separated lead frame 1A and the resin package 4 constitute an individual lead frame substrate 11A (an individual substrate, see FIG. 1A).
Below, as shown to Fig.1 (a), the direction along the mutually orthogonal | vertical side surface in the planar view of the light emitting element 50 is made into the X direction (direction which goes to the right side from the left side of Fig.1 (a)), and Y direction (figure 1). 1 (b) from the lower side to the upper side).
At the center of the resin package 4 is provided a reflector portion 5 which is a hole portion formed by a tapered surface that opens in a circular shape and decreases in diameter toward the inner LED chip mounting portion 2 and the electrical connection area portion 3. It has been.

The separated lead frame 1 </ b> A is a lead for electrically connecting the LED chip 10 with the LED chip mounting portion 2 having pads 2 a formed at one or more places for mounting the LED chip 10. It has the electrical connection area part 3 in which 3a was formed.
The LED chip mounting portion 2 and the electrical connection area portion 3 are opposed to each other in the Y direction with a separation region G on the inner side of the reflector portion 5, and a part of the resin package 4 is disposed in the separation region G extending in the X direction. Is electrically insulated by filling (see FIG. 3).
In the present embodiment, the pad 2 a is provided in a region inside the reflector portion 5 in the LED chip mounting portion 2, and the lead 3 a is provided in a region inside the reflector portion 5 in the electrical connection area portion 3.

As shown in FIG. 4, tie bar portions 6 </ b> X protrude along the X direction at positions adjacent to the separation region G on both side surfaces in the X direction of the LED chip mounting portion 2.
The cross-sectional shape (6b) of the tie bar portion 6X is as shown in FIG. 1B, and the width of the tie bar portion 6X is gradually narrowed at a portion near the bottom surface 4f (described later) of the resin package 4. Is formed. That is, in the present embodiment, the tie bar portion 6X has one surface in the thickness direction aligned with the pad 2a, and the cross-sectional shape of the portion of thickness (t0-t1) (where t1 <t0) is rectangular ( Or a trapezoidal shape), and the cross-sectional shape of the portion of thickness t1 is substantially triangular, and the apex on the side close to the back side of the LED chip mounting portion 2 (the side opposite to the pad 2a) is aligned with the back side. Or is placed slightly inside in the thickness direction.
With such a cross-sectional shape, as shown in FIG. 1B, one tie bar portion 6X is surrounded by the resin package 4 when viewed from the positive X direction. Although not particularly shown, the other tie bar portion 6X is also surrounded by the resin package 4 when viewed from the X direction negative direction.
Further, on both side surfaces in the X direction of the electrical connection area portion 3, tie bar portions 7 </ b> X each having a thickness (t <b> 0-t <b> 1) protrude along the X direction at positions adjacent to the separation region G.
The cross-sectional shape (7b) of the tie bar portion 7X is as shown in FIG. 1B, and the width of the tie bar portion 7X is gradually narrowed at a portion close to the bottom surface 4f (described later) of the resin package 4. Is formed. That is, in the present embodiment, one surface in the thickness direction is aligned with the lead 3a, and the cross-sectional shape of the portion of thickness (t0-t1) (where t1 <t0) is rectangular (or trapezoidal). In addition, the cross-sectional shape of the portion of thickness t1 is substantially triangular, and the apex on the side close to the back surface side (opposite surface of the lead 3a) of the electrical connection area portion 3 is aligned with the back surface or is thick. It is arranged slightly inside in the vertical direction.
With such a cross-sectional shape, as shown in FIG. 1B, one tie bar portion 7X is surrounded by the resin package 4 when viewed from the positive direction of the X direction. Although not particularly shown, the other tie bar portion 7X is also surrounded by the resin package 4 when viewed from the X direction negative direction.

As shown in FIG. 3, the side surface of the LED chip mounting portion 2 on the Y direction negative direction side has a thickness (t0−t1) (where t1 <t0) that is thinner than the thickness t0 of the LED chip mounting portion 2. The tie bar portion 8Y protrudes in the negative Y direction. One side of the tie bar portion 8Y in the thickness direction is aligned with the pad 2a, and the other side of the tie bar portion 8Y in the thickness direction has a step t1 between the LED chip mounting portion 2 and the tie bar portion 8Y. The resin package 4 is filled in the step t1. For this reason, as shown in FIG. 1C, the tie bar portion 8Y is surrounded by the resin package 4 when viewed from the Y direction negative direction.
In addition, a tie bar portion 8Y having a thickness (t0-t1) thinner than the thickness t0 of the electrical connection area 3 also protrudes in the positive direction of the Y direction on the side surface of the electrical connection area 3 on the positive side in the Y direction. Has been. One side of the tie bar portion 8Y in the thickness direction is aligned with the lead 3a, and the other side of the tie bar portion 8Y in the thickness direction has a step t1 between the tie bar portion 8Y and the electrical connection area portion 3. The resin package 4 is filled in the step t1. For this reason, although not particularly illustrated, the tie bar portion 8Y is surrounded by the resin package 4 when viewed from the positive direction in the Y direction.

  In the present embodiment, since the tie bar portion 8Y has a shape that is wider than the thickness, the cross-sectional shape of the tie bar portion 8Y is a shape (rectangular shape or trapezoidal shape) as shown in FIG. However, when the width of the tie bar portion 8Y is narrower, the width of the tie bar portion 8X is gradually narrowed at a portion close to the bottom surface 4f (described later) of the resin package 4 in the same manner as the tie bar portions 6X and 7X described above. It may be formed. In that case, a plurality of tie bar portions 8Y may be formed.

The tie bar portion 6X is cut from a tie bar portion 60 (described later) that connects the LED chip mounting portions 2 in the X direction in the lead frame 1 (described later) before the separated lead frame 1A is separated. Is formed.
The tie bar portion 7X is formed by cutting a later-described tie bar portion 70 that connects the electrical connection area portions 3 in the X direction in the later-described lead frame 1.
The tie bar portion 8Y is formed by cutting a later-described tie bar portion 80 that connects the LED chip mounting portion 2 and the electrical connection area portion 3 in the Y direction in the later-described lead frame 1.

  The surface of the pad 2a and the lead 3a is plated for good bonding of the LED chip 10 and wire bonding to the lead 3a. The type of plating can be freely selected from silver plating, gold plating, palladium plating and the like according to the application. Further, prior to performing silver plating, gold plating, palladium plating, or the like, base plating such as nickel plating having excellent thermal diffusibility may be performed.

The resin package 4 forms the main outer shape of the light emitting element 50. As shown in FIG. 1A, the upper surface 4e covering the periphery of the opening of the reflector portion 5, the X direction negative direction, and the positive direction side Side surfaces 4a and 4b that respectively constitute the side surfaces and side surfaces 4c and 4d that respectively constitute the side surfaces on the Y direction positive direction and the negative direction side are provided.
These side surfaces 4a, 4b, 4c, and 4d are formed by cutting a lead frame 1 described later along the X direction and the Y direction.
For this reason, the cut surfaces 6a, 7a, 6b, 7b, 8c, and 8d, which are cut ends of the tie bar portions 60, 70, and 80 described later, have the cut surfaces 6a and 7a as the side surface 4a and the cut surfaces 6b and 7b as the side surface 4b. The cut surface 8c is aligned with the side surface 4c, and the cut surface 8d is aligned with the side surface 4d.

In addition, as shown in FIG. 2, the surface opposite to the upper surface 4 e in the thickness direction is a region surrounding the outer periphery of the LED chip mounting portion 2 and the electrical connection area portion 3 and a region corresponding to the separation region G. In addition, a bottom surface 4f made of a plane aligned with the surfaces of the LED chip mounting portion 2 and the electrical connection area portion 3 is formed.
For this reason, when the LED chip mounting portion 2 and the electrical connection area portion 3 are viewed from the bottom surface 4 f side, the outer periphery of each is surrounded by the resin package 4.

Examples of the material of the resin package 4 include an epoxy resin, a modified epoxy resin, a silicone resin, an acrylic resin, a polycarbonate resin, an aromatic polyester resin (unsaturated polyester resin), and the like, and one kind of resin is selected from these resins. Or a mixed resin in which a plurality of resins are mixed can be used.
In addition, in order to improve the reflection characteristics in the reflector portion 5, the resin package 4 employs SiO2, TiO2, Al2O3, zirconium oxide, fine particles made of a ceramic material, or a mixture made by mixing one or more of these fine particles. can do. When a mixture is used, the reflectance characteristics can be adjusted to an appropriate reflectance by configuring the mixing ratio. For example, a reflectance of about 90 to 96% can be obtained by combining the above additives.
Moreover, since these additives are hard fine particles, they also have an effect of reinforcing the resin package 4.

In the LED chip 10, an n-pole electrode is bonded to the pad 2 a at a position substantially at the center of the reflector portion 5. In addition, the p-pole electrode of the LED chip 10 is electrically connected to the lead 3a by the bonding wire W.
A transparent resin is filled inside the reflector portion 5 on which the LED chip 10 is mounted to form a transparent resin portion 9, whereby the LED chip 10 is sealed in the transparent resin portion 9. As a material of the transparent resin portion 9, for example, a silicone resin or an epoxy resin can be employed.
For this reason, the LED light excited by the LED chip 10 travels through the transparent resin portion 9 and is reflected by the reflector portion 5, so that it is emitted to the opening side of the reflector portion 5.
In this embodiment, for example, as shown in FIGS. 3 and 4, the surface on the opening side of the transparent resin portion 9 is drawn as a flat surface aligned with the upper surface 4 e of the resin package 4. The surface may be formed in a shape protruding in a dome shape, for example. In this case, since the transparent resin portion 9 has a condensing function, the radiation angle of the LED light can be adjusted to an appropriate radiation angle by the dome shape.

Next, an example of the manufacturing method of the light emitting element 50 of this embodiment is demonstrated.
FIG. 5 is a plan view showing a lead frame substrate for an LED element according to the embodiment of the present invention. 6A and 6B are a plan view and a back view of a lead frame used in the lead frame substrate for an LED element according to the embodiment of the present invention. FIG. 7 is a process flow diagram of manufacturing steps of the LED element lead frame substrate and the light emitting element according to the embodiment of the present invention. FIGS. 8A and 8B are schematic views showing a state of the cutting process of the lead frame substrate for an LED element according to the embodiment of the present invention. Fig.9 (a) is a schematic diagram which shows the mode of the cutting process of a prior art. FIG.9 (b) is a schematic diagram which shows an example of the cut surface after the cutting | disconnection of a prior art. FIG.9 (c) is EE sectional drawing in FIG.9 (b). FIG.9 (d) is a schematic diagram which shows the other example of the cut surface after the cutting | disconnection of a prior art. FIG.9 (e) is FF sectional drawing in FIG.9 (d).

In this method, in order to manufacture the light emitting element 50, one lead frame substrate 11 (LED element lead frame substrate) shown in FIG. 5 is manufactured, and the lead frame substrate 11 is cut into pieces. An individual lead frame substrate 11A, which is a component of the light emitting element 50, is formed.
For this reason, the lead frame substrate 11 is extended in the Y direction so that a plurality of separated lead frame substrates 11A are arranged adjacent to each other in the X direction and the Y direction and cut in the X direction between them. An X-direction cutting allowance CX and a Y-direction cutting allowance CY extended in the X direction for cutting in the Y direction are provided.
The X direction cutting allowance CX and the Y direction cutting allowance CY are strip-like regions equal to the blade width of the dicing blade used for cutting, and are portions removed by cutting.

  In order to manufacture the lead frame substrate 11, the resin package 4 is formed after the lead frame 1 shown in FIGS. 6 (a) and 6 (b) is manufactured. First, the shape of the lead frame 1 will be described.

In the lead frame 1, the LED chip mounting portion 2 and the electrical connection area portion 3 are alternately spaced along a direction (hereinafter simply referred to as Y direction) of the separated lead frame substrate 11A in the Y direction. The LED chip mounting portions 2 and the electrical connection area portions 3 are adjacent to each other along the direction (hereinafter simply referred to as the X direction) of the lead frame substrate 11A that is arranged and separated into pieces. Arranged to fit.
A pair of LED chip mounting portion 2 and electrical connection area portion 3 constituting one individual lead frame 1A, that is, a rectangle (indicated by a two-dot chain line) surrounded by an X-direction cutting margin CX and a Y-direction cutting margin CY. When the LED chip mounting portion 2 and the electrical connection area portion 3 in the figure are referred to as a unit lead frame 1B, there is a separation region G between the LED chip mounting portion 2 and the electrical connection area portion 3 in the unit lead frame 1B. Is formed in the plate thickness direction.

Between the LED chip mounting portions 2 and the electrical connection area portions 3 adjacent to each other with the X-direction cutting margin CX interposed therebetween, the length in the X direction is the X-direction cutting margin at the position where the outer periphery of the hole g is formed. Tie bar portions 60 and 70 (tie bars) that are longer than the width of the CX are respectively installed.
With the tie bar portions 60 and 70 having such a configuration, the LED chip mounting portions 2 and the electrical connection area portions 3 are connected to each other with an interval wider than the width of the X-direction cutting allowance CX.
The tie bar portions 60 and 70 are connected in the Y direction by a tie bar portion 90 having a thickness (t0-t1) that forms the outer periphery in the X direction of the hole g inside the X direction cutting allowance CX. The width of the tie bar portion 90 in the X direction is narrower than the width of the X direction cutting allowance CX.
As shown in FIG. 6 (a), one surface in the thickness direction of the tie bar portions 60, 70, 90 is a surface (hereinafter referred to as the surface of the lead frame 1 and opposite to this). The side surface is referred to as the back surface). Further, the tie bar portions 60 and 70 are formed so that the width thereof gradually becomes narrower at the portion near the back surface of the lead frame 1.

Further, between the LED chip mounting portion 2 and the electrical connection area portion 3 adjacent to each other with the Y-direction cutting margin CY interposed therebetween, the length in the Y direction is longer than the width of the Y-direction cutting margin CY (t0). A tie bar portion 80 (tie bar) defined as -t1) is installed. The tie bar portion 80 may be formed in the shape of a thin square bar similar to the tie bar portions 60 and 70. However, in this embodiment, the tie bar portion 80 is slightly smaller than the width of the LED chip mounting portion 2 and the electrical connection area portion 3 in the X direction. It is provided in a narrow flat plate shape.
With the tie bar portion 80 having such a configuration, the LED chip mounting portion 2 and the electrical connection area portion 3 are coupled to each other with an interval wider than the width of the Y-direction cutting margin CY.
One surface of the tie bar portion 80 in the thickness direction is aligned with the surface of the lead frame 1 as shown in FIG. For this reason, as shown in FIG. 6B, a groove portion s having a depth t <b> 1 is formed on the back surface side of the lead frame 1, which is recessed toward the front surface of the lead frame 1 (in the direction toward the back of the drawing sheet). .

  With such a configuration of the lead frame 1, the lead frame 1 includes a hole h that includes an area where the X direction cutting allowance CX and the Y direction cutting allowance CY intersect, and the X direction cutting allowance CX and the Y direction cutting allowance CY. Is a perforated plate-like member formed with a hole g that crosses a rectangular region surrounded by X in the X direction.

  As shown in FIG. 7, the manufacturing process according to this method includes a first etching process S1, a second etching process S2, a resin package molding process S3, an LED chip mounting process S4, a transparent resin part molding process S5, and a cutting process S6. Prepare.

The first etching step S1 is a step of forming a shape on the surface side of the lead frame 1 by half-etching a metal plate material having a thickness t0 made of a metal alloy such as copper-nickel-tin, for example.
First, a photoresist is applied to one surface of a metal plate material that becomes the surface of the lead frame 1 to form a photoresist layer.
Next, the photoresist layer is exposed through a photomask for pattern exposure that covers the region excluding the holes h and g, and the photoresist layer is developed to remove the photoresist in the non-exposed portion, and hardened as necessary. Perform membrane treatment.
As a result, one surface of the metal plate is covered with the photoresist having the pattern of the region excluding the holes h and g on the surface of the lead frame 1, and the surface corresponding to the holes h and g is not formed with photoresist. Part.

Next, a corrosion-resistant resin film is attached to the other surface of the metal plate material which is the back surface of the lead frame 1, and the photoresist non-formed portion of the metal plate material is formed from one surface side (t0-t1). ) Etching (half-etching treatment) using an etchant such as ferric chloride up to the above depth.
After the half-etching process is completed, cleaning is performed to remove the photoresist and the corrosion-resistant resin film.
Thus, the first etching step S1 is completed.

Next, a second etching step S2 is performed. This step is a step of half-etching the metal plate material to form the shape of the back side of the lead frame 1.
First, a corrosion-resistant resin film is attached to the surface of the lead frame 1.
Next, a photoresist is applied to the other surface of the metal plate material to be the back surface of the lead frame 1 to form a photoresist layer.
Next, the photoresist layer is exposed through a photomask for pattern exposure that covers the holes h and g, a part of the tie bar part 60, a part of 70, and a region excluding 80 and 90, and the photoresist layer is developed. The photoresist in the non-exposed area is removed, and a hardening process is performed as necessary.
As a result, the other surface of the metal plate is covered with a photoresist having a pattern in a region excluding the holes h and g on the back surface of the lead frame 1, a part of the tie bar part 60, a part of 70, and 80 and 90, The back surfaces corresponding to the holes h and g, a part of the tie bar part 60, a part of 70, and 80 and 90 become a photoresist non-formation part.
Here, the portions covered with the photoresist at the tie bar portions 60 and 70 will be described. What is covered with the photoresist on the tie bar portion 60 is the vicinity of the stripe-shaped center line along the X direction of the tie bar portion 60. The same applies to the tie bar portion 70, and the portion covered with the photoresist is in the vicinity of the stripe-shaped center line along the X direction of the tie bar portion 70.
That is, a photoresist having a narrower width than the tie bar portions 60 and 70 is formed in the vicinity of the center line along the X direction of the tie bar portions 60 and 70.

Next, the photoresist non-formed portion of the metal plate material is etched (half-etched) from the other surface side to a depth t1 using an etchant such as ferric chloride.
After the half-etching process is completed, cleaning is performed to remove the photoresist and the corrosion-resistant resin film.
Thereby, in the area | region of the hole h and g, since it etches to the depth which penetrates the hole h and g formed in the said 1st etching process S1, the holes h and g are formed.

Further, since a groove portion having a depth t1 is formed in a region corresponding to the tie bar portion 80, a groove portion s of the lead frame 1 is formed.
Further, the region corresponding to the tie bar portion 90 is etched by the depth t1.
Therefore, the cross-sectional shape of the tie bar portions 80 and 90 is a rectangle (or trapezoid).

In addition, since the photoresist is formed in the vicinity of the center line in the X direction of the tie bar portions 60 and 70, etching does not occur, but the other portions are etched because they are the portions where the photoresist is not formed. As a result, the tie bar portions 60 and 70 are formed in a shape in which the width gradually increases from the other surface side of the metal plate material toward the portion of the depth t1. This is, for example, a pentagonal tie bar having a cross-sectional shape such as a combination of a rectangle (or trapezoid) and a substantially triangular shape as shown by reference numerals 6b and 7b in FIG.
When the tie bar portions 60 and 70 are formed by an etching process, depending on the etching conditions, the side surface portion of the tie bar is not a flat surface but a curved surface, or the corners of the ridge portion of the prismatic tie bar are rounded. However, such a shape may be used.

Therefore, the lead frame 1 is manufactured.
Above, 2nd etching process S2 is complete | finished.

Next, a resin package molding step S3 is performed. This step is a step of forming the resin package 4 on the lead frame 1.
That is, the lead frame 1 is loaded into a recess of a mold for molding the shape of the resin package 4. At this time, the back surface of the lead frame 1 is disposed in close contact with the molding surface of the mold, and the surface of the lead frame 1 has a gap with respect to the molding surface of the mold.
After the lead frame 1 is loaded, the resin material constituting the resin package 4 is filled in the mold by, for example, injection molding and molding is performed.
First, the resin material is filled in the shape of the resin package 4 in a predetermined region other than the pads 2 a and the leads 3 a on the surface of the lead frame 1.
Further, the resin material forming the resin package 4 is filled and solidified so as to go around a gap formed between the recess of the mold and the lead frame. For this reason, the hole parts h and g, the groove part s, and each tie bar part of the lead frame 1 are filled with a resin material. As a result, the tie bar portions 60, 70, 80, 90 are surrounded by the resin material.
When the filling of the resin material is completed and the resin material is solidified, the molded product is removed.
Here, due to the close contact state of the LED chip mounting portion 2, the electrical connection area portion 3 and the mating surface of the mold, for example, a molding burr is generated from the opening lower portion 5a of the reflector portion 5 (see FIG. 5), etc. 5 may be covered with resin. In such a case, the resin on the pad 2a and the lead 3a is removed using an appropriate burr removing means.
Thereby, the lead frame substrate 11 as shown in FIG. 5 is manufactured.
Thus, the resin package molding step S3 is completed.

Next, LED chip mounting step S4 is performed. This step is a step in which after the plating film is formed on each pad 2a and each lead 3a of the lead frame substrate 11, the LED chip 10 is mounted on the pad 2a and wired to the lead 3a.
First, silver plating, gold plating, palladium plating, or the like is applied to the pad 2a and the lead 3a by electrolytic plating or electroless plating.
Next, the n-pole electrode of the LED chip 10 is bonded to the pad 2a, and the p-pole electrode of the bonded LED chip 10 is wired to the lead 3a by the bonding wire W.
Thus, the LED chip mounting step S4 is completed.

Next, a transparent resin part molding step S5 is performed. This step is a step of filling each reflector portion 5 of the lead frame substrate 11 on which the LED chip 10 is mounted with the transparent resin portion 9 to seal the LED chip 10 and solidifying the transparent resin portion 9.
For example, when a silicone resin is used as the material of the transparent resin portion 9, the resin is filled in the reflector portion 5 in a liquid state and then solidified by heating.
The transparent resin part molding step S5 is thus completed.

Next, cutting process S6 is performed. In this step, the lead frame substrate 11 is set in a cutting device such as a dicing device, and is cut at the X direction cutting allowance CX and the Y direction cutting allowance CY. It is a manufacturing process.
For example, when the lead frame substrate 11 is cut at the X-direction cutting allowance CX, as shown in FIG. 8A, the dicing blade 20 of the dicing apparatus is rotated in one direction to move the X-direction cutting allowance CX along the Y-direction. To move.
At this time, the inside of the X-direction cutting allowance CX includes, in addition to the resin package 4, tie bar portions 60 and 70 that cross the X-direction cutting allowance CX in the X direction, and the inside of the X-direction cutting allowance CX along the Y direction. There is an extending tie bar portion 90 (see FIG. 6B).
For this reason, when the dicing blade 20 passes through the lead frame substrate 11, the lead frame substrate 11 is divided along the X-direction cutting margin CX to form a cut end. At this time, the cut edges of the resin package 4 correspond to the surfaces to be the side surfaces 4b and 4a of the separated lead frame substrate 11A.
Further, the tie bar portions 60 and 70 are divided into tie bar portions 6X and 7X, respectively, and cut surfaces 6b and 7b (see FIG. 8B) aligned with the side surface 4b on the side surface 4b side as a cut end. On the side surface 4a side (not shown in FIG. 8B), cut surfaces 6a and 7a which are the same plane as the side surface 4a are formed.
Further, the tie bar portion 90 is crushed and disappears. Thereby, the LED chip mounting portion 2 and the electrical connection area portion 3 in the unit lead frame 1B are also separated and electrically insulated by the resin package 4 in the separation region G.

Although not particularly illustrated, similarly, if cutting is performed at the Y-direction cutting allowance CY, the side surfaces 4c and 4d are formed by the cut edge of the resin package 4, and the tie bar portion 80 is cut so that the two tie bars are cut. Cut surfaces 8c and 8d that are divided into the portion 8Y and are aligned in the same plane as the side surfaces 4c and 4d are formed.
In this way, a plurality of separated lead frame substrates 11 A are manufactured from the lead frame substrate 11.
The cutting step S6 is thus completed.
In this way, the light emitting element 50 is manufactured.

In the lead frame substrate 11 of this embodiment that is cut in this step, the tie bar portions 60, 70, and 80 are all surrounded by the resin package 4. For this reason, since the resin package 4 adheres to the outer periphery of the tie bar portions 60, 70, 80, deformation of the outer peripheral surface of each tie bar portion is suppressed. Therefore, even when a shearing force is applied to the metal material in the direction of rotation of the dicing blade 20 during cutting, sagging on the cut surface can be suppressed.
As a result, there is no possibility that the metal peels off from the sag portion and foreign matter is generated, so that it is possible to prevent abnormalities and defects such as a short circuit in the subsequent assembly process.

Further, the tie bar portion can be increased in strength as the cross-sectional area is increased, whereby the strength of the lead frame substrate 11 can be maintained.
Therefore, as in the case of the tie bar portions 60 and 70, the periphery is surrounded by the resin package 4, and the width is formed so as to be gradually narrowed in the portion near the bottom surface 4f of the resin package. Thus, it is possible to obtain a tie bar portion that ensures strength while suppressing sagging on the cut surface.

Such an operation of the present embodiment will be described in comparison with the prior art.
As shown in FIG. 9A, the lead frame substrate 101 according to the prior art is, for example, one in which a lead frame having tie bar portions 160 and 170 crossing the X-direction cutting allowance CX is integrally formed with the resin package 4. It is.
Since these tie bar portions 160 and 170 are formed with the same thickness as the metal plate material forming the lead frame, the back surface 101b of the lead frame is molded in contact with the mold surface. For this reason, the metal surface M having ductility is exposed on the back surface 101b side without being surrounded by the resin material.
With such a configuration, for example, when the dicing blade 20 is rotated in the L direction in FIG. 9A, the metal surface M is cut by the shearing force of the dicing blade 20 as shown in FIGS. 9B and 9C. It is pushed toward 160a and 170a to form a sag d1.
When the dicing blade 20 is rotated in the R direction in FIG. 9A, the metal surface M is dragged outward by the shearing force of the dicing blade 20 to the outside as shown in FIGS. 9D and 9E. As a result, sagging d2 is formed.
Accordingly, the metal may peel from the sagging d1, d2, etc., and foreign matter may be generated, so that abnormalities and defects such as a short circuit in the subsequent assembly process are likely to occur.

According to the present embodiment, since the lead frame substrate 11A in which the light emitting element 50 is separated is manufactured by cutting the lead frame substrate 11, sagging occurs on the cut surfaces of the tie bar portions 60, 70, 80 at the time of cutting. Since it does not occur, it can be prevented that the metal peels off from the sag portion of the cut surface and becomes a foreign substance. For this reason, in LED chip mounting process S4, malfunctions, such as a short circuit and a contact failure, can be prevented, for example.
Further, since no sag portion is generated, the metal of the sag portion does not protrude toward the bottom surface 4f of the light emitting element 50, for example, and the dimensional accuracy of the outer shape of the light emitting element 50 is improved.

In the above description, the example in which the cutting step S6 is performed after the transparent resin portion molding step S5 has been described has been described. However, the resin package molding step S3 is performed, so that the periphery of the tie bar portion becomes the resin package 4. If it is after being surrounded, cutting process S6 can be performed at an appropriate time.
For example, the cutting step S6 may be performed between the resin package molding step S3 and the LED chip mounting step S4, or the cutting step S6 is performed after performing the LED chip mounting step S4 after the resin package molding step S3. May be.

Further, in the above description, in order to manufacture the lead frame 1, the example of performing the first etching step S <b> 1 and the second etching step S <b> 2 in which half etching processing is performed has been described, but the lead frame 1 is manufactured. The etching process is not limited to this.
For example, the order of the first etching step S1 and the second etching step S2 may be switched.
Moreover, you may make it perform one half etching from the surface and back surface of a metal plate material simultaneously.
Further, after forming the holes h and g by the full etching process, the shape of the groove part s of the tie bar part 80 and the back side of the tie bar parts 60, 70 and 90 is formed by the half etching process from the back side. Also good.

  In the above description, the shape of the back side of the tie bar portions 60, 70, 80, 90 has been described as an example in the case of forming by half-etching processing, but it may be formed by removal processing such as machining or laser processing. Good.

  Further, all the components described in the above embodiment can be implemented by appropriately changing or deleting the combination within the scope of the technical idea of the present invention.

DESCRIPTION OF SYMBOLS 1 Lead frame 1A Separated lead frame 1B Unit lead frame 2 LED chip mounting part 2a Pad 3 Electrical connection area part 3a Lead 4 Resin package (resin part)
4f Bottom surface 5 Reflector part 6X, 7X, 8Y Tie bar part 60, 70, 80 Tie bar part (tie bar)
6a, 6b, 7a, 7b, 8c, 8d Cut surface 9 Transparent resin portion 10 LED chip 11 Lead frame substrate 11A Separated lead frame substrate (individual substrate)
50 Light emitting element CX X direction cutting allowance CY Y direction cutting allowance G Separation region g, h Hole M Metal surface s Groove S1 First etching step S2 Second etching step S3 Resin package forming step S4 Cutting step S5 LED chip mounting step S6 Transparent resin part molding process W Bonding wire

Claims (3)

An LED chip mounting portion having a pad on which the LED chip is mounted;
A lead frame in which a plurality of electrical connection area portions, which are arranged apart from the LED chip mounting portion and form leads that are electrically connected to the LED chip, are connected by tie bars;
An LED element for manufacturing an individual substrate by cutting the tie bar together with the resin portion, and a resin portion that covers a portion of the lead frame excluding the LED chip mounting portion and a part of the electrical connection area portion Leadframe substrate for
The tie bar extends longer than the cutting allowance, is formed so as to be surrounded by the outer periphery of the resin portion, and the width of the tie bar is gradually reduced at a portion close to the outer surface of the resin portion. A lead frame substrate for an LED element, wherein   The lead frame substrate for an LED element according to claim 1, wherein the tie bar is formed by half etching.     An LED chip is mounted on the individual substrate manufactured by cutting the tie bar of the lead frame substrate for an LED element according to claim 1 or 2.

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