JPS6315483A - Lead frame for light-emitting diode - Google Patents

Abstract

PURPOSE:To suppress dispertion of light and improve the light emitting efficiency by laminating LED elements and making the LED elements have positive and negative electrodes at the same side face. CONSTITUTION:At the tip of an anode lead members 10, a leveled face 11 and a reflected part 12 are formed in a body, One of the electrode parts of an LED is placed on the leveled face 11 and the reflected part 12 has a dike-shaped frame and surrounds about half of the LED in the vicinity of the side circumference face of its LED to be put by the electrodes. Even at the tip of a cathode lead members, the leveled face 21 and the reflected part 22 are formed in a body. The other electrode part of the LED is placed on the leveled face 21 and the reflected part 22 has the dike-shaped frame composing a remained other half of the LED and together with the reflected part 12 surrounds full circumferences of the side circumference face of its LED in the vicinity of the side circumference face of the LED to be put by the electrodes. In addition, the reflected parts 12 and 22 of both lead members 10 and 20 as well as all the surface of the leveled faces 11 and 21 are processed by silver plating and plated layers 13 and 23 are formed. Thus, the above members and others are so laminated that the light emitted in a direction along laminated layer faces having both positive and negative electrodes at the same side face are not dispersed and permit them to reflect in a right angle to laminated faces. As a result, the above performance of the lead frame drastically improves the light emitting efficiency.

Description

[Detailed description of the invention] [Industrial application field 1 The present invention relates to a lead frame for a light emitting diode.

[Prior Art] Conventionally, lead frames for light emitting diodes (hereinafter referred to as rLEDJ) are suitable for LEDs in which a pair of positive and negative electrode portions are separated on both sides, and are lead frames shown in FIGS. 5 to 7. It has been known.

Here, Figure 5 shows I! A perspective view of the lead frame during construction,
FIG. 6 is a sectional view of a lead frame obtained by cutting and shaping the lead frame shown in FIG. 5, and FIG. 7 is a sectional view of the lead frame with an LED attached thereto. This board frame 10
1 is composed of a pair of positive and negative lead members 110 and 120 arranged in parallel with a distance between them. One lead member 110 is integrally formed with a flat part 111 on which the LED 130 is placed at its tip, and a bank-like reflective part 112 surrounding the side peripheral surface of the LED 130 placed therein. The other lead member 120 is disposed such that its tip protrudes beyond the tip of the embankment-shaped reflective portion 112 of one lead member 110.

FIG. 7 shows a state in which the LED 130 is attached to this lead frame 101. In this case, the LED 130 is
An electrode portion on one side is adhered and placed on a flat portion 111 of one lead member 110 having a reflective portion using a conductive paste 140. The electrically excavated portion on the other side is connected to the tip of the other lead member 120 and the gold wire 1.
50.

By the way, recently, using gallium nitride (GaN) as an element, a blue color L E with a pair of positive and negative m poles on the same side.
D As shown in the figure, a lead frame is used that is composed of a pair of positive and negative lead members 210 and 220 with flat tips. The GaN blue LEDs 230 are arranged in parallel to each other, and both N-shaped portions of the GaN blue LEDs 230 are adhered and placed on both end faces with conductive paste 240, respectively.

[Problems to be solved by the invention] However, GaN blue LEDs are 1-GaN, n-GaN
and sub-eye 1F substrates are laminated, and n-GaN is passed through the hole provided in a part of i-(3aN, +-a
Both electrode portions made of 1-GaN and n-GaN are formed on the surface on the taN side. When electricity is applied and it emits light, blue light is emitted from between the i-GON and the n-QaN in a direction along the laminated surface. Therefore, the light is dispersed into the surroundings,
A problem has arisen in that the luminous efficiency is very poor.

The present invention is intended to overcome the above-mentioned problems, and aims to provide a lead frame with good luminous efficiency and suitable for an LED having both positive and negative electrode parts on the same side.

[Means for Solving the Problems] The present invention provides a flat part on which one electrode part of a light emitting diode having a pair of positive and negative electrode parts on the same side is formed integrally with the flat part. a positive and negative lead member, which is provided at a distance from one lead member, and a reflective portion provided near at least one side of the light emitting diode to be used; The present invention is characterized in that it has a configuration in which the other lead member, positive and negative, has a flat part on which an electrode part is placed.

The reflective portion that characterizes the lead frame of the present invention has directionality in a certain direction so that the light emitted from the 16-layer LED, which has both positive and negative electrodes on the same side, is not dispersed. This reflective part is located near the side circumferential surface of the LED.
and is formed integrally with the flat portion of at least one lead member. In this case, the reflective part is formed of a reflective part integrally formed with the flat part of one lead member and a reflective part integrally formed with the flat part of the other lead member.
It can be configured to surround almost the entire side circumferential surface of the ED. Alternatively, the reflecting portion may be formed integrally with only the flat portion of one of the lead members so as to surround the entire side circumferential surface of the LED. The reflective portion has a reflective surface inside thereof that slopes outward as it rises from the flat portion. This reflective surface is LED 8! It is preferable to set the angle close to 45 degrees with respect to the IWa surface because light is reflected in a direction along the longitudinal direction of the lead member. Further, it is preferable to silver plate at least the reflective surface of the reflective part, as this will improve reflection efficiency.

The lead frame of the present invention having a reflective portion in this way is
Any LED that is stacked and has both positive and negative electrode parts on the same and negative sides can be applied not only to GaN.

[Function] The LED used in the lead frame for a light emitting diode of the present invention has LED elements laminated and has both positive and negative electrodes on the same side. In such an LED, light is emitted from the stacked elements in a direction along the stacked surface. Then, the emitted light is reflected by the reflection part and travels in a direction that is approximately perpendicular to the mi plane. Therefore, light is not dispersed to the surroundings, and luminous efficiency is improved.

[Example] Hereinafter, specific embodiments of the present invention will be described based on the drawings.

(Example 1) Figures 1 to 3 show a lead frame for a light emitting diode according to Example 1. Figure 1 is a perspective view of the lead frame during manufacture, and Figure 2 is a view of Figure 1. FIG. 3 is a cross-sectional view of a pair of positive and negative lead members obtained by cutting and shaping the lead frame shown in FIG.

The lead frame of this embodiment has one lead member (hereinafter referred to as "anode lead member J") 10 connected to the anode side, and the other lead member (hereinafter referred to as "cathode lead member") 20 connected to the cathode side. It depends on. At the tip of the anode lead member 1o, a flat part 11 on which one electrode part of the LED is placed, and a bank-like reflecting part 12 that surrounds approximately half of the side circumferential surface of the LED to be placed are integrated. Some of them are formed in

Also at the tip of the cathode lead member, there is a flat part 21 on which the other electrode part of l-Eo is placed, and a side part of 1-ED along with the bank-shaped reflective part 12 near the side peripheral surface of the LED to be placed. The remaining approximately half of the embankment-like reflecting portion 22 that surrounds approximately the entire circumference of the surface is integrally formed. The entire surfaces of the reflective portions 12.22 and flat portions 11.21 of both lead members 10.20 are plated with silver to form a plating layer 13.23.

Both lead parts 010 and 20 formed in this way are
The flat parts 11.21 are arranged in parallel so that they are substantially the same. In this state, GaN is placed on the flat part 11.21.
A blue LED 30 is mounted and adhered with a conductive paste 40.

The GaN blue LED 30 is made of n-Ga on a sapphire substrate.
N1 High resistance r-aaN further doped with Zn to compensate
It is made by growing. A part of the n-GaN 32 is penetrated into a hole provided in a part of the 1-GaN 31 so that the surface of the n-GaN 32 is substantially flush with the surface of the i-GaN 31. This partially penetrated n-GaN32 and 1-
A pair of positive and negative electrode portions are formed on the same side of the GaN 31. This GaN blue 1-ED30 is n
-GaN 32 is placed on the flat part 21 of the cathode lead member 20,
i-GaN 31 is adhered and placed on the flat portion 11 of the anode lead member 10, respectively.

LED 30 according to this embodiment formed as described above
Then, a current with a voltage of 7.5 cm was applied from the lead member 10.

Then, LED 30 emitted light, and a bright and good blue light was observed. This is i-GaN31 and n-GaN
This is because the blue light emitted from between 32 and 32 is not reflected by the reflecting portions 12 and 22 and dispersed, resulting in a significant improvement in luminous efficiency. Further, in this example, since only the reflective portion was plated with silver, there was an advantage that the manufacturing cost did not increase much.

(Actual Mf942) FIG. 4 shows a sectional view of a lead frame according to the second embodiment. In this embodiment, a series of bank-shaped reflecting portions 52 are formed. This reflective portion 52 is formed integrally with only the flat portion 51 of the anode lead member 50. The tip of the cathode lead member 60 has a flat portion 61 on which the LED is placed.
is formed so as to partially protrude from the tip surface. The other parts are formed similarly to the lead frame of the above embodiment.

This cathode lead member 60 is arranged in parallel with the anode lead member 50 at a position slightly separated from the anode lead member 50 so that both flat portions 51.61 of both lead members 50.60 are substantially the same. There is.

The same GaN blue LED 30 used in Example 1 was adhered to this lead frame using conductive paste 70, and a current of 7.5 V was applied to the lead frame. As in the case of Example 1, extremely good blue light could be observed as a result. It should be noted that since the reflecting section of this embodiment is formed in a series without any gaps, compared to the anti-a+ section of Embodiment 1, the reflection 9)r ratio is improved due to the lack of gaps.

[Effects of the Invention] As explained above, the lead frame for a light emitting diode of the present invention has a pair of positive and negative leads on the same side. [a flat part on which one electrode part of the light emitting diode having the i part is placed; a reflective part formed integrally with the flat part and provided near the peripheral surface of at least one side of the light emitting diode on which it is placed; and the other positive and negative lead member, which is spaced apart from the one lead member and has a flat part on which at least the other electrode part of the light emitting diode is placed. Teru. This makes it possible to use LEDs that are stacked and have both positive and negative electrodes on the same surface, and to reflect light emitted in a direction along the stacked surface in a direction perpendicular to the stacked surface without being dispersed. Therefore, luminous efficiency is greatly improved and visibility is improved when used as an indicator light.

[Brief explanation of drawings]

1 to 3 show a lead frame according to Example 1 of the present invention, and FIG. 1 is a perspective view of the lead frame at the time of manufacture;
Figure 2 is a cross-sectional view of a lead frame obtained by cutting and shaping the lead frame shown in Figure 1, Figure 3 is a cross-sectional view of a GaN blue LED mounted on the lead frame, and Figure 4 is an example. 2, FIGS. 5 to 8 show conventional lead frames, FIG. 5 is a perspective view of the lead frame when assembled, and FIG. 6 is the lead frame shown in FIG. 5. Figure 7 is a cross-sectional view of the lead frame obtained by cutting and shaping the lead frame, Figure 7 is a cross-sectional view of the LED mounted on the lead frame, Figure 8 is a conventional LED with a pair of positive and negative electrodes on the same side. FIG. 3 is a cross-sectional view of the device attached to a glued frame. 1.101...Lead frame 10.50.110...Anode lead member 20.60.
120... Cathode lead member 11.21.51.61.
111...Flat part 12.22.52.112...Reflection part 13.23...Plating layer 30.230...GaN blue light emitting diode (GaN
Blue LED) 3 1-i -G a N 32-n - G a N 33... Saffi A7 board 40.70.140.240-i#Electric paste 130
...Light emitting diode (LED) 150...Gold wire Patent applicant Yutaka 1 Gosei Co., Ltd. Agent Patent attorney Hirodo Okawa Patent attorney Akio Maruyama Figure 3 Figure 4 Figure 5 Figure 6 Figure 8

Claims (4)

[Claims] (1) A flat part on which one of the electrode parts of a light emitting diode having a pair of positive and negative electrode parts on the same side is placed, and at least one of the light emitting diodes which is formed integrally with the flat part and placed on it. a positive and negative lead member comprising a reflective part provided near the circumferential surface of the part, and a flat surface provided at a distance from the one lead member and on which at least the other electrode part of the light emitting diode is placed. 1. A lead frame for a light emitting diode, characterized in that the lead frame has a positive and a negative lead member having a positive and a negative lead member. (2) The other lead member has a reflective part formed integrally with the flat part and provided near the remaining side peripheral surface of the light emitting diode to be mounted, and the reflective part of the one lead member and the reflective part Claim 1, wherein the reflecting portion of the other lead member surrounds almost the entire side circumferential surface of the light emitting diode.
Lead frame for light-emitting diodes as described in section. (3) The lead frame for a light emitting diode according to claim 2, wherein the reflecting portion has a reflecting surface on the inside that slopes outward as it rises. (4) The lead frame for a light emitting diode according to claim 3, wherein the reflective portion is plated with silver at least on its inner peripheral surface side.