JP2002170997A - Semiconductor light emitting device with protective element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light emitting device with protective element which can be manufactured simply. SOLUTION: The semiconductor light emitting device 10 with protective element comprises a substrate 12 having a surface on which leads 14a and 14b are formed. A composite chip 30 integrating an LED chip 16, a reflection film 18 and a ZD chip 20 is die bonded onto the substrate 12 (leads 14a and 14b). Subsequently, the p side electrode 16a of the LED chip 16 is connected electrically with the lead 14a through a bonding wire 24a and the n side electrode 16b is connected electrically with the lead 14b through a bonding wire 24b. The ZD chip 20 is bonded with a polarity reverse to that of the LED chip 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor light emitting device with a protection element, and more particularly, to a light emitting element chip (LED chip) and an LED chip.
The present invention relates to a semiconductor light emitting device with a protection element, comprising a protection element chip (zener diode chip) for protecting an ED chip.

[0002]

2. Description of the Related Art An example of a conventional semiconductor light emitting device of this type is disclosed in Japanese Patent Application Laid-Open Publication No. Hei.
No. 1-507182 [H01S 3/18, H01L
33/00]. As shown in FIG. 4, in the semiconductor integrated circuit 1, a light emitting diode (LED) is disposed on a protection circuit (protection diode) 2 having a protection pn junction such as a Zener diode (ZD) via a metal layer 3. ) Are bonded (die-bonded) to a device 4 having an active pn junction. The conductive device contacting portion 4 a provided on the upper surface of the device 4 is electrically connected to the bonding surface 5 provided on the semiconductor supporting portion 2 a having the n region of the protection diode 2 via a bond wire 6. It is connected to the.

[0003] Another example is disclosed in Japanese Patent Application Laid-Open No. H11-214747 [H01] filed on Aug. 6, 1999.
L 33/00, H01L 21/60 301]. As shown in FIG. 5, in the semiconductor light emitting device 11, a wiring pattern 15 formed on a substrate 13 is formed.
a a static electricity protection element lead frame 17 such as ZD
Is mounted (die bond). A flip-chip type semiconductor light-emitting element (LED) 19 is mounted on the upper surface of the electrostatic protection element 17 in such a manner that p-side and n-side electrodes are electrically connected to each other by micro bumps 21 with opposite polarities. Further, the wire 23 is electrically connected to the wiring pattern 15b from the bonding surface 17b formed on the p-side electrode 17a of the electrostatic protection element 17 formed in a step shape and lower than the mounting surface of the semiconductor light emitting element 19. Have been.

In the semiconductor integrated circuit 1 and the semiconductor light emitting device 11, light such as a laser or infrared light is emitted from the LED 4 (15) in the top direction and the side direction.
Further, the ZD2 (13) prevents static electricity (surge) from being generated in the LED 4 (15) and prevents an overcurrent from flowing through the LED 4 (15), and prevents the LED 4 (15) from being damaged or destroyed. Was.

[0005]

However, in this prior art, in the former case, the bond wire 6 is connected from the LED chip to the ZD chip, that is, the protection diode 2 is connected from the contact portion 4a on the device 4. Since the wire bonding is performed in a narrow area such as the bonding surface 5 provided on the semiconductor supporting portion 2a, there is a problem that the wire bonding is difficult.

In the latter case, there is no difficulty in wire bonding as in the former case.
Since bump connection is made to an unstable place such as on a chip, bump connection is difficult.

[0007] As described above, in each case, the production was difficult.

[0008] Therefore, a main object of the present invention is to provide a semiconductor light emitting device with a protection element which can be easily manufactured.

[0009]

According to a first aspect of the present invention, there is provided a substrate having two first electrodes, a protection element chip having a second electrode connected to each of the first electrodes, and a protection element chip disposed on the protection element chip. A semiconductor light-emitting device with a protection element, comprising: a light-emitting element chip having two third electrodes on an upper surface thereof; and performing wire bonding from the third electrode to the first electrode.

According to a second aspect of the present invention, there is provided a substrate having two first electrodes, a light emitting element chip having a second electrode connected to each of the first electrodes, and two light emitting element chips arranged on the light emitting element chip and provided on the upper surface. A semiconductor light emitting device with a protection element, comprising: a protection element chip having a third electrode; and performing wire bonding from the third electrode to the first electrode.

According to a third aspect of the present invention, there is provided a substrate having two first electrodes, the first die being bonded to one of the first electrodes, and
A protection element chip having an upper surface electrode and a lower surface electrode connected to each of the electrodes, and a second region having substantially the same size as the first region other than the first region where the upper surface electrode is formed on the protection element chip; A light-emitting element chip having two second electrodes on the upper surface thereof, the upper electrode being formed to be substantially the same size as the first region, the lower electrode being connected to one of the first electrodes, and the upper electrode being connected to the first electrode. A semiconductor light emitting device with a protection element, wherein wire bonding is performed to the other of the electrodes, and wire bonding is performed from the second electrode to one of the first electrode and each of the upper electrodes.

[0012]

The semiconductor light emitting device with a protection element of the first invention includes a substrate, and two first electrodes are formed on the surface of the substrate.
On this substrate, a protection element chip such as a Zener diode chip having a second electrode connected to the two first electrodes is bonded. That is, the second electrode is provided on the lower surface of the protection element chip. A light emitting element chip such as an LED chip having two third electrodes is provided on the protection element chip. For example, a composite chip in which a light emitting element chip and a protection element chip are integrally formed can be die-bonded on a substrate. Further, the third electrode and the first electrode of the light emitting element chip are electrically connected by a bonding wire. That is, wire bonding is performed from the light emitting element chip to the electrode on the substrate. Therefore, the composite chip can be bonded relatively easily.

A semiconductor light emitting device with a protection element according to a second aspect of the invention includes the same substrate as in the first aspect of the invention. On this substrate, a light emitting element chip having a second electrode connected to each of the first electrodes is bonded. A protection element chip having two third electrodes on the upper surface is bonded on the light emitting element chip. For example, a composite chip can be die-bonded on a substrate as in the first invention. Further, the third electrode and the first electrode of the protection element chip are electrically connected by bonding wires. That is, wire bonding is performed from the protection element chip to the electrode on the substrate. Therefore, similarly to the semiconductor light emitting device with a protection element of the first invention, the composite chip can be bonded relatively easily.

The semiconductor light emitting device with a protection element of the third invention also uses the same substrate as in the first invention, and a protection element chip is die-bonded to one of the first electrodes on the substrate. The protection element chip is provided with an upper surface electrode and a lower surface electrode. The lower electrode is connected to one of the first electrodes, and the upper electrode is connected to the other of the first electrodes. Also,
The upper surface of the protection element chip has a first region in which an upper surface electrode is formed and a second region having substantially the same size as the first region.
The light emitting element chip is arranged (adhered) in the second region. That is, the protection element chip is formed larger than the light emitting element chip, and the upper surface electrode is formed to have substantially the same size as the first region. That is, the upper surface electrode is formed relatively large. Also, the light emitting element chip has two second electrodes on the upper surface, one of the second electrodes is connected to one of the first electrodes, and the second
The other of the electrodes is connected to the top electrode. For example, when a composite chip in which a protective element chip and a light emitting element chip are formed in a composite manner is die-bonded to one of the first electrodes,
The lower surface electrode of the protection element chip is in contact with (connected to) one of the first electrodes. The upper electrode is wire-bonded to the other of the first electrodes, and the second electrode is wire-bonded to one of the first electrodes and the upper electrode. Since the upper electrode is formed relatively large, wire bonding can be easily performed even when wire bonding is performed from the light emitting element chip to the protection element chip.
Therefore, similarly to the first and second aspects, the composite chip can be bonded relatively easily.

In the semiconductor light-emitting device with a protection element according to the invention, if a reflection film is provided between the protection element chip and the light-emitting element chip, light emitted from the light-emitting element chip toward the protection element chip is reflected. Since the light can be radiated to the outside, it is possible to prevent the luminous efficiency from lowering. In this case, the composite chip is a light emitting element chip,
It is formed by the protection element chip and the reflection film.

For example, the reflection film can be formed of a non-conductive white material such as titanium oxide. Further, it may be formed by mixing boron nitride (BN) into a paste (adhesive).

[0017]

According to these inventions, since the light emitting element chip and the protection element chip can be bonded relatively easily, manufacturing is simple.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a semiconductor light emitting device with a protection element (hereinafter simply referred to as "light emitting device") 10 of this embodiment.
Includes an insulating substrate (hereinafter simply referred to as “substrate”) 12 formed of glass epoxy or ceramic.
The substrate 12 is provided with two electrodes (leads) 14a and leads 14b formed of, for example, copper foil. As can be seen from FIG. 1, the leads 14a and 14b extend from the upper surface of the substrate 12 to the lower surface via the side surfaces.

In FIG. 1, the leads 14a and 14b are given a thickness for easy understanding.

The light emitting device 10 has a light emitting element chip (L
ED chip) 16, reflective film 18, and chip (ZD chip) 2 of a protection element such as a Zener diode (ZD)
Contains 0. In this embodiment, the ZD chip 20 is die-bonded (adhered) to the substrate 12 (leads 14a and 14b) with an adhesive 22 such as silver paste.
The reflection film 18 is formed on the D chip 20. Further, the LED chip 16 is bonded (adhered) on the reflection film 18.

The LED chip 16 has an active pn junction. On the upper surface of the LED chip 16, two electrodes (p-side electrode 16a and n-side electrode 16b) connected to each of the leads 14a and 14b are provided. Provided. In this embodiment, the p-side electrode 16a and the lead 14a are electrically connected by a bonding wire 24a such as a gold wire.
The side electrode 16b and the lead 14b are connected to the bonding wire 2
4b, they are electrically connected.

The reflection film 18 is formed of a metal oxide such as titanium oxide which is white and has non-conductivity. However, the reflection film 18 is made of boron night light (B
N) may be formed by mixing a paste (adhesive).

In FIG. 1, the reflection film 18 is provided with a thickness for easy understanding, but is actually formed in a thin film shape.

The reflection film 18 is formed on the LED chip 1.
6 can be reflected. That is,
The reflection film 18 has reflectivity to the LED chip 16. On the other hand, the reflection film 18 has a light shielding property with respect to the ZD chip 20.

The ZD chip 20 has a pn junction for protection and is omitted in FIG. 1, but two electrodes (a p-side electrode 20a and an n-side electrode 20a) are provided on the lower surface of the ZD chip 20.
b) is formed. In this embodiment, the p-side electrode 20
a is connected to the lead 14b, and the n-side electrode 20b is connected to the lead 14a.

That is, the LED chip 16 and the ZD chip 2
It is arranged with a polarity opposite to 0, and is connected in parallel to the leads 14a and 14b.

The light emitting device 10 further includes a light transmitting resin 26 such as an epoxy resin, and the light transmitting resin 26
Formed on top. That is, the translucent resin 26 seals the LED chip 16, the reflection film 18, the ZD chip 20, and the bonding wires 24a and 24b.

The light emitting device 10 is used in an electronic device (not shown) such as a mobile phone or a motherboard, and is mounted on a circuit board (printed board) of the electronic device. Therefore, when a voltage is applied between the leads 14a and 14b, light such as laser or infrared light is emitted (emitted) from the LED chip 16 in the direction (emission direction) shown in FIG. That is, light is emitted in the top direction and the side direction of the light emitting device 10.

Light emitted from the LED chip 16 in the lower direction is reflected by the reflection film 18 and emitted in the upper direction or the side direction. That is, since the light emitted from the LED chip 16 in the lower direction is not absorbed by the ZD chip 20, it is possible to prevent the luminous efficiency from lowering.

Further, while the LED chip 16 is emitting light, the ZD chip 20 prevents the static electricity (surge) from being generated in the LED chip 16 and causes the LED chip 16 to emit light.
This prevents an overvoltage from being applied to the ED chip 16 and an overcurrent from flowing. In this way, damage or destruction of the LED chip 16 is avoided.

For example, when such a light emitting device 10 is formed (manufactured), first, a composite chip 30 in which the LED chip 16, the reflection film 18 and the ZD chip 20 are formed integrally (composite) is formed on a substrate. 12 is die-bonded.

The ZD chip 20, the reflection film 18 and the LED chip 16 may be bonded on the substrate 12 in order.

As can be seen from the ZD chip 20 shown in another embodiment (FIG. 2A) described later, the p-side electrode 20
Since the a and n-side electrodes 20b are counter electrodes and are provided at the ends of the ZD chip 20, even if the die bonding position of the composite chip 30 is shifted (error), defects such as poor contact or short-circuit occur. There is very little to do. Therefore, die bonding can be easily performed.

Subsequently, the p-side electrode 16 of the LED chip 16
The a and n-side electrodes 16b are connected to the lead 14a and the lead 1
4b is electrically connected to each other by bonding wires 24a and 24b. That is,
Wire bonding is performed. As described above, after the composite chip 30 (the LED chip 16, the reflection film 18, and the ZD chip 20) is bonded onto the substrate 12, the translucent resin 26 is molded.

According to this embodiment, since the composite chip is die-bonded to the lead on the substrate and the LED chip is wire-bonded to the lead, the composite chip can be relatively easily bonded. Therefore, the light emitting device can be easily manufactured.

Further, since the reflection film is formed between the ZD chip and the LED chip, it is possible to prevent the luminous efficiency of the LED chip from lowering. That is, the luminous efficiency can be improved as compared with the light emitting device shown in FIGS.

Light emitting device 1 of another embodiment shown in FIG.
0 is the same as the embodiment of FIG. 1 except that the bonding position between the ZD chip 20 and the LED chip 16 is different.
Duplicate description is omitted.

A light emitting device 10 of another embodiment is shown in FIG.
The LED chip 16 is connected to the substrate 12 by the bump 32 as shown in FIG. In other words, in another embodiment, the LED chip 16 is arranged upside down from the embodiment of FIG. 1, the p-side electrode 16a is bump-connected to the lead 14a, and the n-side electrode 16b is bump-connected to the lead 14b. This LED
A reflection film 18 is formed on the chip 16, and the reflection film 18
The ZD chip 20 is bonded thereon. As can be seen from FIGS. 2A and 2B, the ZD chip 20 is also arranged upside down from the embodiment of FIG.
Two electrodes (p-side electrode 20a and n-side electrode 20b) are provided. The p-side electrode 20a is connected to the lead 14b by a bonding wire 24a, and the n-side electrode 20b is connected to the lead 14a by a bonding wire 24b. That is, in another embodiment, the composite chip 30 ′ obtained by inverting the composite chip 30 shown in FIG.
And bonded to the lead 14b.

The light emitting device 10 of another embodiment is also applied to an electronic device such as a mobile phone or a motherboard, and is mounted on a printed circuit board of the electronic device. Therefore, when a voltage is applied between the leads 14a and 14b, L
Light is emitted from the ED chip 16 in a light emitting direction as shown in FIG. That is, the light emitted from the LED chip 16 is applied to almost the side surface of the light emitting device 10.
Light emitted from the LED chip 16 toward the upper surface is reflected by the reflective film 18 and emitted from the side surface of the light emitting device 10 to the outside of the light emitting device 10. However, the LED chip 16
Is emitted by the substrate 12.

For example, when manufacturing the light emitting device 10 of another embodiment, a composite chip 30 ′ in which the LED chip 16, the reflective film 18 and the ZD chip 20 are formed on the substrate 12 is formed on the substrate 12. And the bonding wire 24a and the bonding wire 24b are electrically connected to the lead 14a and the lead 14b from the ZD chip 20, respectively. That is, wire bonding is performed. Then, the translucent resin 26 is molded.

The LED chip 16, the reflection film 18, and the ZD chip 20 may be bonded on the substrate 12 in order.

The LED chip 1 shown in FIG.
As is clear from FIG. 6, the p-side electrode 16a and the n-side electrode 16b are provided on the counter electrode with a step, so that even if the bonding position of the composite chip 30 'is shifted (error), there is a problem such as poor contact or short circuit. The problem described above hardly occurs. In addition, since the LED chip 16 is bonded (bump-connected) to a stable place such as on the substrate 12, bump connection can be easily performed.

According to another embodiment, since the composite chip is bump-connected to the lead on the substrate and wire-bonded from the ZD chip to the lead, the composite chip can be bonded relatively easily. That is, similarly to the embodiment of FIG. 1, the light emitting device can be easily manufactured.

Further, since the light emitted from the LED chip in the upper direction is reflected by the reflection film and emitted from the side of the light emitting device, the luminous efficiency can be improved as much as possible.

A light emitting device 10 of another embodiment shown in FIG. 3A has a ZD chip 2 having an upper electrode and a lower electrode.
1 is substantially the same as that of the embodiment of FIG. 1 except that the bonding method of the composite chip is different.

In this light emitting device 10, as shown in FIG. 3A, the lead 14a is formed in a substantially convex shape on the upper surface of the substrate 12, and the ZD chip 20 is attached to the lead 14a by the adhesive 2.
2 are bonded (bonded). ZD chip 2
Numeral 0 is formed as shown in FIG. 3B, and has an upper surface electrode, that is, a p-side electrode 20a, and a lower surface electrode, that is, an n-side electrode 20b, as described above. The p-side electrode 20a is
It is formed in the first region 34a on the upper surface of the ZD chip 20.
In other embodiments, the n-side electrode 20b is formed on the entire lower surface of the ZD chip 20.

The n-side electrode 20b is connected to the ZD chip 20
May be formed on a part of the lower surface of the lead 14a.
In order to perform die bonding on the entire surface, the device is provided on the entire lower surface.

The ZD chip 20 has a first region 34a
And a second region 34b substantially the same size as (or slightly larger than the first region 34a).
b, the LED chip 16 is provided via the reflection film 18.

Further, the p-side electrode 16a provided on the upper surface of the LED chip 16 and the lead 14a are electrically connected by a bonding wire 24a. On the other hand, the n-side electrode 16b provided on the upper surface of the LED chip 16 and the ZD chip 2
The 0 upper surface electrode, that is, the p-side electrode 20a is electrically connected by a bonding wire 24b. Further, the p-side electrode 20a of the ZD chip 20 and the lead 14 are electrically connected by a bonding wire 24c.

As can be seen from FIGS. 3A and 3B, the ZD chip 20 is formed larger than the LED chip 16. Also, the p-side electrode 20a is in the first region 3
Since it is formed with the same size (area) as 4a, it is formed relatively large. Therefore, LED chip 16 and Z
The D chip 20 is connected by the bonding wire 24b. However, since the p-side electrode 20a is formed relatively large, the bonding wire 24b is easily wire-bonded as compared with the case shown in FIG. be able to. Further, as shown in FIG. 5, since the LED chip 16 is not bump-connected on the ZD chip 20, the bonding of the LED chip 16 is simple.

The light emitting device 10 of another embodiment is also used for an electronic device such as a mobile phone or a motherboard, and is mounted on a printed circuit board of the electronic device. Therefore, when a voltage is applied between the lead 14a and the lead 14b, light such as laser or infrared light is emitted (emitted) from the LED chip 16 in the direction (light emission direction) shown in FIG. That is, light is emitted in the top direction and the side direction of the light emitting device 10.

Light emitted from the LED chip 16 in the lower direction is reflected by the reflection film 18 and emitted in the upper direction or the side direction. That is, since the light emitted from the LED chip 16 in the lower direction is not absorbed by the ZD chip 20, it is possible to prevent the luminous efficiency from lowering.

When manufacturing such a light emitting device 10, first, the composite chip 3 in which the LED chip 16, the reflection film 18 and the ZD chip 20 are formed integrally (composite)
0 ″ is die-bonded on the substrate 12, that is, on the lead 14a.

The ZD chip 20, the reflection film 18, and the LED chip 16 may be sequentially bonded on the leads 14a.

Subsequently, the bonding wires 24a to 24a
c is wire-bonded. That is, the p-side electrode 16a of the LED chip 16 is electrically connected to the lead 14a, the n-side electrode 16b of the LED chip 16 is electrically connected to the p-side electrode of the ZD chip 20, and the p-side electrode of the ZD chip 20 is connected. The electrode and the lead 14b are electrically connected. As described above, after the ZD chip 20, the reflective film 18, and the LED chip 16 are bonded on the substrate 12, the translucent resin 26 is molded.

According to another embodiment, the composite chip is die-bonded to one lead on the substrate, wire-bonded from the LED chip to one lead on the substrate, and the upper electrode of the relatively large ZD chip is formed. Wire bonding, and then wire bonding from the upper surface electrode to the other lead, so that the composite chip can be bonded relatively easily. That is, the light emitting device can be easily manufactured.

Further, since the reflection film is formed between the ZD chip and the LED chip, it is possible to prevent the luminous efficiency of the LED chip from lowering. That is, the luminous efficiency can be improved as compared with the light emitting device shown in FIGS.

In these embodiments, the reflection film is provided between the LED chip and the ZD chip in order to improve the luminous efficiency. However, when the luminous efficiency is not considered, the LED chip and the ZD chip are used. And a non-reflective non-conductive adhesive to form a composite chip.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;

FIG. 2 is an illustrative view showing one embodiment of another invention;

FIG. 3 is an illustrative view showing one embodiment of another invention;

FIG. 4 is an illustrative view showing one example of a conventional light emitting device.

FIG. 5 is an illustrative view showing another example of the conventional light emitting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Semiconductor light emitting device with a protection element 12 ... Substrate 14a, 14b ... Lead 16 ... LED chip 18 ... Reflection film 20 ... ZD chip 24a, 24b, 24c ... Bonding wire 26 ... Translucent resin 30, 30 ', 30 "... Composite chip 32… Bump

Claims (5)

[Claims] 1. A substrate having two first electrodes, a protection element chip having a second electrode connected to each of the first electrodes, and two third electrodes disposed on the protection element chip and provided on the upper surface. A semiconductor light emitting device with a protection element, comprising: a light emitting element chip having electrodes; and wire bonding from the third electrode to the first electrode. 2. A substrate having two first electrodes, a light emitting element chip having a second electrode connected to each of the first electrodes, and a third light emitting element disposed on the light emitting element chip and having an upper surface formed of two third electrodes. A semiconductor light emitting device with a protection element, comprising: a protection element chip having an electrode, wherein wire bonding is performed from the third electrode to the first electrode. 3. A substrate having two first electrodes, a protection element chip having an upper surface electrode and a lower surface electrode die-bonded to one of the first electrodes and connected to each of the first electrodes, and A second region, which is substantially the same size as the first region other than the first region where the upper surface electrode is formed on the protection element chip, and which has two
A light emitting element chip having two second electrodes, the upper surface electrode is formed to be substantially the same size as the first region, the lower surface electrode is connected to one of the first electrodes, and the upper surface electrode is connected to the first electrode. A semiconductor light emitting device with a protection element, wherein wire bonding is performed to the other of the electrodes, and wire bonding is performed from the second electrode to each of the one of the first electrodes and the upper surface electrode. 4. The semiconductor light emitting device with a protection element according to claim 1, further comprising a reflection film between said protection element chip and said light emitting element chip. 5. The semiconductor light emitting device with a protection element according to claim 4, wherein said reflection film includes a non-conductive white material.