JPH11150295A - Semiconductor light-emitting element, production of the semiconductor light-emitting element, and indicator thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively pick up light emitted from a light-emitting layer by providing a conductive layer between a pair of electrode leads and a P electrode, in such a manner as to connect to a P electrode a pair of electrode leads which are provided with a recessed part for a semiconductor chip whose surface which is a reflecting face of light-emitting from a light-emitting layer and are insulated/divided. SOLUTION: A recessed part 5 for a semiconductor chip is provided to a pair of electrode lead consisting of a P-electrode 1 and an N-electrode lead 2. For example, a semiconductor chip 3 which is provided with a light emitting layer formed by a P-N junction of P-type semiconductor layer made of a GaN and an N-type semiconductor layer is fitted to the recessed part. The P-type semiconductor layer is connected to the P electrode lead 1, while the N-type semiconductor layer is connected to the N-electrode lead 2. The joint part between the semiconductor chip 3 and the P-type electrode lead 1 and N electrode 2 is formed of visible optically transmissive epoxy resin, etc., and it is encapsulated with an encapsulating resin 4 which functions as a lens. A light emitted from the light-emitting layer is reflected on the surface of the recessed part, and it can be extracted effectively, because no wire bonding or thin film electrode blocking the light is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor light emitting device, a method for manufacturing a semiconductor light emitting device, and a display device using the semiconductor light emitting device.

[0002]

2. Description of the Related Art Conventionally, among the light-emitting diodes used in outdoor display devices requiring high luminance, for example, blue and green light-emitting diodes have a structure shown in FIG. 9, for example. For example, an N electrode of a semiconductor chip 23 having a light emitting layer formed by a PN junction of GaN and an N electrode lead 21 are connected by a thin wire 25 made of, for example, gold. On the other hand, the P electrode of the semiconductor chip 23 and the P electrode lead 22 are also connected by a thin gold wire 26. The connection portion between the semiconductor chip 23 and the N electrode lead 21 and the P electrode lead 22 is made of a visible light transmitting epoxy resin containing a filler such as aluminum oxide or magnesium oxide, and has a role of a lens. It is sealed with a resin 24. The lens power of the sealing resin 24 is set differently in a direction parallel to the drawing and in a direction perpendicular to the drawing. For example, the power in the direction parallel to the drawing is weaker.

FIG. 10A is an enlarged plan view of a main part of the light emitting diode, and FIG. 10B is a sectional view taken along line BB ′ in FIG. 10A. Reflector surfaces 27 and 27 'are formed on the N-electrode lead 21, and the semiconductor chip 23 is adhered to a concave portion formed by the reflector surfaces 27 and 27' by an adhesive layer 36 such as a resin. The semiconductor chip 23 includes, for example, a sapphire substrate 28 and a GaN PN junction J formed on the sapphire substrate 28, the N electrode 30 formed on the upper surface thereof is connected to the N electrode lead 21 by a wire 25, and the P electrode 34 is The wires 26 are connected to the P electrode leads 22 respectively. The area of the semiconductor chip 23 other than the N electrode 30 is the light emitting area E.

FIG. 11 is a sectional view showing the semiconductor chip 23 further enlarged. For example, an N-type GaN layer 29 is formed on an upper layer of a sapphire substrate 28, an N electrode 30 made of, for example, aluminum is formed on the upper layer, and a wire 25 connected to an N electrode lead is further connected. On the other hand, in a region excluding the N electrode 30, N-type GaN
The layer 29 is formed to have a large thickness, and a P-type GaN layer 32 is formed thereover via an active layer 31 to form a PN junction. On the upper layer, a first P electrode 33 made of, for example, a translucent thin film of gold and a second P electrode 34 made of the same gold and formed thicker than the first P electrode 33 are formed, and are connected to P electrode leads. Wire 26 is connected. A protective insulating film 35 made of, for example, silicon oxide or aluminum oxide is formed on the chip surface.

The above light emitting diode is sealed with a sealing resin. For example, when the light emitting diode is used for an indoor display device, for example, GaN of GaN is formed on a printed circuit board without using a reflector or a lens in order to increase the pixel density. In some cases, a semiconductor chip having a light emitting layer based on a PN junction is formed by direct conductive bonding.

[0006]

However, in the above-mentioned conventional light emitting diode, since the electrode is formed on the light emitting layer, the light transmittance is reduced. In particular, the wire bonding portion occupying about 1/3 of the total light emitting area cannot directly take out light at all. For this reason, only 35 to 62% of the light transmittance can directly extract light. Although some light is reflected by the reflector and comes out on the entire surface, it cannot be said that the generated light is still effectively extracted.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is therefore an object of the present invention to provide a semiconductor light emitting device capable of effectively extracting light generated from a light emitting layer, and a method of manufacturing a semiconductor light emitting device. And a display device using the semiconductor light emitting element.

[0008]

In order to achieve the above object, a semiconductor light emitting device according to the present invention is formed by laminating a P-type semiconductor layer and an N-type semiconductor layer, wherein the P-type semiconductor layer and the N-type semiconductor layer are stacked. A light emitting layer that emits light by applying a predetermined voltage between the type semiconductor layers; a semiconductor chip having a P electrode and an N electrode connected to the P type semiconductor layer and the N type semiconductor layer, respectively; A pair of electrode leads having the concave portion for a semiconductor chip serving as a reflecting surface of light emitted from the light emitting layer and being divided so as to be insulated from each other;
A conductive layer disposed between the pair of electrode leads and the P electrode or the N electrode so as to connect the pair of electrode leads and the P electrode or the N electrode;

In the above semiconductor light emitting device, a light emitting layer in which a P-type semiconductor layer and an N-type semiconductor layer are laminated, and a semiconductor having a P electrode and an N electrode connected to the P-type semiconductor layer and the N-type semiconductor layer, respectively. The chip is mounted in the recess of the pair of electrode leads, and the pair of electrode leads and the P or N electrode are connected by a conductive layer disposed between the pair of electrode leads and the P or N electrode. I have. The light emitting layer is P
Light is emitted by applying a predetermined voltage between the type semiconductor layer and the N-type semiconductor layer, and a part of the light is reflected on the concave surface of the electrode lead.

According to the above-described semiconductor light emitting device, the semiconductor chip and the electrode lead are connected by the conductive layer disposed between them, and the wire bonding or the half bonding for blocking light from the light emitting layer such as a conventional light emitting diode is performed. Since there is no transparent thin film electrode, light extraction efficiency is improved.

Further, since the thickness of the P electrode and the N electrode can be made sufficiently large, the light reflectance at the electrode portion is increased, so that the light extraction efficiency is improved, and the light at the bottom of the concave portion of the electrode lead is reduced. The need to increase the reflectance is reduced, and the concave bottom surface is not required to be a mirror surface, so that the manufacturing cost of the electrode lead can be suppressed.

The light-emitting layer generates heat when energized. In a conventional semiconductor light-emitting device, this heat is conducted to the electrode lead mainly through the sapphire substrate and the adhesive layer or through a thin gold wire, and the heat is radiated. Is done. For this reason, heat dissipation was insufficient, but in the semiconductor light emitting device of the present invention, by using a heat conductive material such as a metal as the conductive layer, heat generated by energization of the light emitting layer was directly conducted to the electrode leads. In this case, heat can be dissipated, and the heat dissipation efficiency can be improved. Further, since the thickness of the P electrode and the N electrode can be made sufficiently large, the electric resistance of the electrode portion can be reduced, and the amount of heat generated at the electrode portion can be reduced. Furthermore, it is possible to use an opaque, low thermal resistance material that has been proven in ordinary semiconductor devices as an underfill sealant that absorbs thermal stress due to the difference in the thermal expansion coefficient between the semiconductor chip and the bottom of the concave part of the electrode lead. Become.

In the above-mentioned semiconductor light-emitting device, the light-emitting layer is preferably formed on a light-transmitting insulating substrate. Thus, light emitted from the light-emitting layer passes through the insulating substrate, so that the efficiency of extracting light emitted from the light-emitting layer can be improved.

In the above-mentioned semiconductor light emitting device, preferably, the pair of electrode leads have a substantially plane-symmetric shape. Preferably, the pair of electrode leads is divided at diagonal positions of the semiconductor chip. By forming the electrode lead in such a structure, the concave portion can be easily formed, the cost of parts can be reduced, and the alignment of the semiconductor chip and the electrode lead becomes easy, so that the optical axis can be easily taken. .

In the semiconductor light emitting device described above, preferably, the bottom surface of the concave portion of the pair of electrode leads is substantially similar to the shape of the semiconductor chip. Preferably, the semiconductor chip has a substantially square shape, the bottom shape of the concave portion of the one electrode lead has a triangular shape, and the angle of the apex angle of the triangle forms the apex angle of the semiconductor chip. Same as angle. By adjusting the bottom shape of the concave portion of the electrode lead to the shape of the semiconductor chip, the alignment of the semiconductor chip and the electrode lead becomes easy.

In the above semiconductor light emitting device, preferably, the depth of the concave portion of the electrode lead and the thickness of the semiconductor chip are substantially the same. Light from the side surface of the semiconductor chip can be effectively extracted by reflection on the inclined surface of the side wall of the concave portion of the electrode lead, and the jig holding the semiconductor chip does not hit the side wall because the concave side wall is too high. , Positioning can be performed accurately.

In the above-mentioned semiconductor light emitting device, preferably, the surface of the concave portion of the electrode lead is formed substantially as a mirror surface for reflecting light emitted from the light emitting layer. Preferably, the side wall surface of the concave portion surface of the electrode lead has a tapered shape that becomes wider toward the opening side. By making the concave surface of the electrode lead a mirror surface, substantially all of the light emitted from the light emitting layer is reflected. Also, the light emitted from the light emitting layer is formed by making the side wall surface tapered upward. Can be effectively reflected in one direction, and the light extraction efficiency from the semiconductor chip can be improved.

In the above semiconductor light emitting device, preferably, a positioning hole for the semiconductor chip is formed in the bottom surface of the concave portion of the electrode lead, and the hole is connected to the P electrode or the N electrode. It is embedded with a conductor. This facilitates the alignment between the semiconductor chip and the electrode leads.

Preferably, in the semiconductor light emitting device, the P light is removed except for a region connected to the electrode lead by a conductor.
The electrode and the N electrode are covered with an insulator having poor wettability to the conductor. As a result, the P electrode and the N electrode can be protected, and effects such as electromigration can be prevented. Further, when connecting the semiconductor chip and the electrode leads using a molten metal such as solder, self-alignment is achieved. Positioning can be performed.

Preferably, in the semiconductor light emitting device, at least three protrusions for positioning the bottom surface of the concave portion and the bonding surface of the P-type semiconductor layer and the N-type semiconductor layer of the semiconductor chip substantially in parallel are provided. The pair of electrode leads are formed on the bottom surface of the concave portion. Due to manufacturing variations, the axis of the semiconductor chip deviates from the axis of the concave surface (reflector), or the axis of the semiconductor chip deviates from the axis of the sealing resin lens. Assembling a display device using light-emitting diodes that vary in the direction in which the display becomes uneven will impair the uniformity of the screen. However, by forming projections on the bottom surface of the recess for positioning, the semiconductor chip and the surface of the recess (reflector) are formed. ) Or alignment of the sealing resin with the lens (axis angle alignment) becomes easier,
Variations in the direction of the maximum luminance can be suppressed.

In the above semiconductor light emitting device, preferably, the conductive layer is an anisotropic conductive material. An anisotropic conductive film or a coating layer of an anisotropic conductive material can be a conductive layer that connects a pair of electrode leads to a P electrode or an N electrode. In this case, connection, positioning, and fixing of the semiconductor chip to the electrode lead can be performed at the same time, so that the process can be simplified and the semiconductor chip can be easily manufactured.

According to another aspect of the present invention, there is provided a method for manufacturing a semiconductor light emitting device, comprising the steps of: bonding a N-type semiconductor layer and a P-type semiconductor layer on a light-transmitting insulating wafer; Forming a light-emitting layer that emits light by applying a predetermined voltage between the P-type semiconductor layer and the N-type semiconductor layer; and forming a P electrode connected to the P-type semiconductor layer; A step of forming an N electrode connected to the N-type semiconductor layer, a step of covering the P electrode and the N electrode to form an anisotropic conductive layer, and dicing the wafer into individual semiconductor chips And a pair of electrode leads having the concave portion for the semiconductor chip, the surface of which is a reflection surface of light emitted from the light emitting layer, and being divided so as to be insulated from each other. The P electrode or the N electrode To connect via a serial anisotropic conductive layer, and a step of fixing the semiconductor chip.

According to the method of manufacturing a semiconductor light emitting device of the present invention described above, an N-type semiconductor layer and a P-type semiconductor layer are bonded on a light-transmitting insulating wafer, and the P-type semiconductor layer and the N-type semiconductor A light-emitting layer that emits light by applying a predetermined voltage between the layers is formed, a P-electrode connected to the P-type semiconductor layer is formed, and an N-electrode connected to the N-type semiconductor layer is formed. Thereafter, the P electrode and the N electrode are covered to form an anisotropic conductive layer, and the wafer is diced to be divided into individual semiconductor chips. Next, a pair of electrode leads having a concave portion for a semiconductor chip whose surface is a reflection surface of light emitted from the light emitting layer and divided so as to be insulated from each other are provided on a pair of electrode leads and a P electrode or The semiconductor chip is fixed so that the N electrodes are connected via the anisotropic conductive layer.

According to the method for manufacturing a semiconductor light emitting device of the present invention, the semiconductor chip and the electrode leads are connected by the anisotropic conductive layer. Since there is no thin film electrode and the thickness of the P electrode and the N electrode can be made sufficiently large, the light reflectance at the electrode portion is increased, and a semiconductor light emitting device with improved light extraction efficiency is manufactured. be able to. Since the necessity of increasing the light reflectance on the bottom surface of the concave portion of the electrode lead is reduced, the concave bottom surface does not have to be a mirror surface, so that the manufacturing cost of the electrode lead can be reduced. Further, since the anisotropic conductive layer is formed before the wafer dicing step, manufacturing is easy, and connection, positioning and fixing of the semiconductor chip to the electrode lead can be performed at the same time. It can be easily manufactured.

In order to achieve the above object, a method for manufacturing a semiconductor light emitting device according to the present invention is a method for manufacturing a semiconductor light emitting device, comprising the steps of: bonding a N-type semiconductor layer and a P-type semiconductor layer on a light-transmitting insulating wafer; Forming a light-emitting layer that emits light by applying a predetermined voltage between the P-type semiconductor layer and the N-type semiconductor layer; and forming a P electrode connected to the P-type semiconductor layer; Forming an N-electrode connected to the N-type semiconductor layer, forming a grid-like slit in the wafer, forming the anisotropic conductive layer by covering the P-electrode and the N-electrode, A step of expanding the slit portion of the wafer to divide the semiconductor chip into individual semiconductor chips, and the semiconductor chip concave portion whose surface is a reflection surface of light emitted from the light emitting layer, and is divided so as to be insulated from each other. The above-mentioned pair of electrode leads The P electrode or the N electrode and the pair of electrode leads so as to be connected through the anisotropic conductive layer, and a step of fixing the semiconductor chip.

A joined body of an N-type semiconductor layer and a P-type semiconductor layer on a light-transmitting insulating wafer, wherein the P-type semiconductor layer
A light emitting layer that emits light by applying a predetermined voltage between the type semiconductor layers is formed, a P electrode connected to the P type semiconductor layer is formed, and an N electrode connected to the N type semiconductor layer is formed.
Thereafter, a lattice-shaped slit is formed in the wafer to cover the P electrode and the N electrode to form an anisotropic conductive layer. Then, the slit portion of the wafer is expanded and divided into individual semiconductor chips.
Next, a pair of electrode leads having a concave portion for a semiconductor chip whose surface is a reflection surface of light emitted from the light emitting layer and divided so as to be insulated from each other are provided on a pair of electrode leads and a P electrode or The semiconductor chip is fixed so that the N electrodes are connected via the anisotropic conductive layer.

According to the method of manufacturing a semiconductor light emitting device of the present invention described above, the semiconductor chip and the electrode leads are connected by the anisotropic conductive layer. Since there is no thin film electrode and the thickness of the P electrode and the N electrode can be made sufficiently large, the light reflectance at the electrode portion is increased, and a semiconductor light emitting device with improved light extraction efficiency is manufactured. be able to. Since the necessity of increasing the light reflectance on the bottom surface of the concave portion of the electrode lead is reduced, the concave bottom surface does not have to be a mirror surface, so that the manufacturing cost of the electrode lead can be reduced. In addition, since the anisotropic conductive layer is formed before dividing the wafer into individual semiconductor chips, manufacturing is easy, and connection, positioning, and fixing of the semiconductor chips to the electrode leads can be performed at the same time. The process can be simplified and easily manufactured.

In order to achieve the above object, a display device of the present invention is formed by laminating a P-type semiconductor layer and an N-type semiconductor layer, and is provided between the P-type semiconductor layer and the N-type semiconductor layer. A light emitting layer that emits light by applying a predetermined voltage to the semiconductor chip, a semiconductor chip having a P electrode and an N electrode connected to the P-type semiconductor layer and the N-type semiconductor layer, respectively, and a light emitted from the light emitting layer on the surface. A pair of electrode leads having the concave portion for the semiconductor chip serving as a reflection surface and being divided so as to be insulated from each other; and connecting the pair of electrode leads to the P electrode or the N electrode. Above 1
A plurality of semiconductor light emitting devices each having a pair of electrode leads and a conductive layer disposed between the P electrode or the N electrode are arranged in a matrix.

The above-described display device is formed by arranging a plurality of semiconductor light emitting elements in a matrix. The semiconductor light emitting element includes a light emitting layer in which a P-type semiconductor layer and an N-type semiconductor layer are stacked, and a P-type semiconductor layer. A semiconductor chip having a P electrode and an N electrode connected to the semiconductor layer and the N-type semiconductor layer, respectively, is mounted in a recess of the pair of electrode leads, and is disposed between the pair of electrode leads and the P electrode or the N electrode. The pair of electrode leads and the P electrode or the N electrode are connected by the conductive layer, and the light emitting layer emits light by applying a predetermined voltage between the P type semiconductor layer and the N type semiconductor layer. Are reflected on the concave surface of the electrode lead.

According to the above-described display device, each semiconductor light-emitting element constituting the display device is connected with the semiconductor chip and the electrode lead by the conductive layer disposed between the semiconductor chip and the electrode lead. Since there is no wire bonding for shielding light or a translucent thin film electrode, light extraction efficiency is improved.

Further, by using a heat conductive material such as a metal as the conductive layer, heat generated by energization of the light emitting layer can be directly conducted to the electrode lead and radiated, thereby improving heat radiation efficiency. .

In the above display device, preferably, the positional relationship between the P electrode and the N electrode of the plurality of semiconductor light emitting elements is aligned in one direction. Preferably, the light emission centers of the plurality of semiconductor light emitting elements are aligned on the upper side. Also,
Preferably, the split surfaces of the pair of electrode leads are aligned so as to be substantially horizontal. This makes it possible to increase the viewing angle in the lower direction than the upper direction of the screen of the display device and in the horizontal direction than in the vertical direction.

[0033]

Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment FIG. 1 is a sectional view of a semiconductor light emitting device according to the first embodiment. A pair of electrode leads including a P electrode lead 1 and an N electrode lead 2 is provided with a recess for a semiconductor chip, for example, a GaN P-type semiconductor layer and an N-type semiconductor layer PN.
A semiconductor chip 3 having a light emitting layer formed by bonding is mounted in the recess, and the P-type semiconductor layer and the P-electrode lead 1 are connected, while the N-type semiconductor layer and the N-electrode lead 2 are connected. A connection portion between the semiconductor chip 3 and the P electrode lead 1 and the N electrode lead 2 is made of a visible light transmitting epoxy resin or the like, and is sealed by a sealing resin 4 having a role of a lens.

FIG. 2A is an enlarged plan view of a main part of the semiconductor light emitting device, and FIG. 2B is a cross-sectional view taken along line AA 'in FIG. 2A. A concave portion whose surface is a reflection surface of light emitted from the light emitting layer of the semiconductor chip 3 is formed on a pair of electrode leads, which are substantially symmetrical in shape and are symmetrically arranged and include a P electrode lead 1 and an N electrode lead 2. And the semiconductor chip 3 is mounted. The bottom of the recess 5 '
Is substantially similar to the semiconductor chip 3 having a substantially square shape, is slightly larger than the semiconductor chip 3, and the bottom shape of one electrode lead is a substantially isosceles right triangle. Also, the side wall surface 5 of the concave portion of the electrode lead is approximately 45
It is formed of a slope inclined at an angle, and has a tapered shape that becomes wider toward the opening side. It is preferable that at least the side wall surface of the concave portion of the electrode lead is a mirror surface that reflects most of the light emitted from the light emitting layer of the semiconductor chip 3. Positioning holes H1 and H2 are opened near the right angles of the bottom surfaces of the substantially isosceles right triangles of the individual electrode leads at the connection portion with the semiconductor chip, and near the long sides of the bottom surface. At least three or more positioning projections 15 are formed on a pair of electrode leads, and two projections are formed on each electrode lead (four in total).

The semiconductor chip 3 is arranged on the projection 15. The semiconductor chip 3 is composed of, for example, a sapphire substrate 6 and a PN junction J of GaN. For example, the semiconductor chip 3 is made of a metal such as solder or a conductive adhesive so as to be connected to the P-type semiconductor layer in the PN junction. A conductive hemispherical conductive layer 12 is formed and is buried in the hole H1 on the bottom surface of the concave portion of the P electrode lead 1. Similarly,
Hemispherical conductive layer 13 that is also thermally conductive to the N-type semiconductor layer
Is formed and is buried in the hole H2 on the bottom surface of the concave portion of the N electrode lead 2. Areas other than the conductive layers 12 and 13 are sealed with an underfill sealant 14, and the semiconductor chip 3 is fixed to the bottom of the recess using the underfill sealant 14 as an adhesive. In the semiconductor chip 3, a region other than the conductive layer 13 connected to the N electrode is a light emitting region E. The depth of the concave portion and the thickness of the semiconductor chip 3 are substantially the same, and the height of the surface of the semiconductor chip and the surface of the electrode lead on the light emitting surface side are substantially the same.

FIG. 3 is a sectional view showing the vicinity of the semiconductor chip 3 further enlarged. For example, an N-type semiconductor layer 7 made of N-type GaN is formed under a transparent sapphire substrate 6 which is light-transmitting, and an N-type semiconductor layer
An electrode 10 is formed and is connected via a conductive layer 13 at a hole H2 on the bottom surface of the N electrode lead 2. On the other hand, in a region other than the N-electrode 10, the N-type semiconductor layer 7 and the P-type GaN P-type semiconductor layer 8 are stacked. Below the P-type semiconductor layer 8, a P-electrode 9 made of, for example, gold, which is connected to the P-type semiconductor layer 8, is formed to have a uniform thickness and a large thickness. The connection is made at the hole H1 on the surface. The uniform thickness of the P electrode allows the lower surface of the light emitting layer to be a completely reflecting surface. Further, the P electrode 9 and the N electrode 13 are formed by covering with a protective insulating film 11 made of, for example, silicon oxide or aluminum oxide, so that effects such as electromigration can be prevented. Further, the gap between the semiconductor chip and the electrode lead is sealed with an underfill sealant 14.

According to the light emitting element of the present embodiment, the semiconductor chip and the electrode lead are connected by the conductive layer disposed therebetween, and the conventional wire bonding or half bonding for blocking light from the light emitting layer is performed. Since there is no transparent thin film electrode, light extraction efficiency is improved. In addition, a positioning hole is formed in the bottom surface of the concave portion of the electrode lead at a portion connecting the electrode lead and the conductive layer, and a positioning protrusion is formed on the bottom surface. ) Or the alignment of the sealing resin with the lens is facilitated, and variations in the direction of maximum brightness can be suppressed.

In addition, by using a heat conductive material such as a metal as the conductive layer, heat generated by energization of the light emitting layer can be directly conducted to the electrode lead and radiated, thereby improving heat radiation efficiency. . Further, since the thickness of the P electrode and the N electrode can be made sufficiently large, the electric resistance of the electrode portion can be reduced, and the amount of heat generated at the electrode portion can be reduced. Furthermore, it is possible to use an opaque, low thermal resistance material that has been proven in ordinary semiconductor devices as an underfill sealant that absorbs thermal stress due to the difference in the thermal expansion coefficient between the semiconductor chip and the bottom of the concave part of the electrode lead. Become.

Further, in the conventional semiconductor light emitting device, light emitted from the back surface side of the semiconductor chip is reflected on the reflector surface (surface of the electrode lead concave portion) through an adhesive layer such as an epoxy resin, and exits toward the opening side of the concave portion. However, since the light emitted from the semiconductor chip irradiates the adhesive layer and changes its color to a color such as brown, the light emitted from the semiconductor light-emitting element is particularly absorbed by the adhesive layer, thereby shortening the life of the semiconductor light-emitting element. However, in the semiconductor light emitting device of the present embodiment described above, the light emitting layer side surfaces of the P electrode and the N electrode serve as reflection surfaces, and emitted light does not substantially reach the adhesive layer or the underfill sealant. The above problem can be avoided, and the life can be made longer than before.

Second Embodiment The semiconductor light emitting device according to the second embodiment is the first light emitting device shown in FIG.
This is substantially the same as the semiconductor light emitting device of the embodiment. FIG. 4 is an enlarged plan view of a main part of the semiconductor light emitting device of the present embodiment.
FIG. 4A is a cross-sectional view taken along the line AA ′ in FIG. Unlike the semiconductor light emitting device of the first embodiment, no positioning hole is formed in the connection portion with each electrode lead semiconductor chip, and a positioning projection is formed near the long side of the bottom surface. Not. The P electrode connected to the P-type semiconductor layer in the PN junction has a P electrode projection 16 formed thereon, and the N electrode has an N electrode projection 17 formed thereon. For example, the P-electrode protrusion 16 is connected to the P-electrode lead 1 and the N-electrode protrusion 17 is connected to the N-electrode lead 2 via an anisotropic conductive layer 18 made of an anisotropic conductive film. And an anisotropic conductive layer 18 between the N electrodes
Insulated by Further, the semiconductor chip 3 is fixed to the bottom of the concave portion of the electrode lead by the anisotropic conductive layer 18.

FIG. 5 shows a further enlarged sectional view of the vicinity of the semiconductor chip 3. For example, an N-type semiconductor layer 7 made of N-type GaN is formed under a transparent sapphire substrate 6 which is light-transmitting, and an N-type semiconductor layer
The electrode 10 and the N-electrode projection 17 are formed, while the N-type semiconductor layer 7 and the P-type GaN P-type semiconductor layer 8 are laminated in a region other than the N-electrode 10. Under the P-type semiconductor layer 8, a P-electrode 9 made of, for example, gold connected to the P-type semiconductor layer 8 is formed with a uniform thickness and thick, and a P-electrode projection 16 is formed under the P-electrode 9. I have. The above-mentioned P electrode 9, P electrode convex portion 16, N electrode 10, and N electrode convex portion 1
Reference numeral 7 denotes an anisotropic conductive layer 1 made of, for example, an anisotropic conductive film.
8. The anisotropic conductive layers below the P-electrode protrusions 16 and the N-electrode protrusions 17 are crushed and thinned, and the conductive particles (indicated by black dots in the figure) in the anisotropic conductive layers are underneath. Electrode lead 1 and P electrode protrusion 1
6 or between the N electrode lead 2 and the N electrode projection 17.

The semiconductor light emitting device of this embodiment described above comprises an anisotropic conductive film or an anisotropic conductive layer formed by applying an anisotropic conductive material, and a pair of electrode leads and a P electrode or an N electrode. Since it is a conductive layer to be connected, connection, positioning, and fixing of the semiconductor chip to the electrode lead can be performed simultaneously, so that the process can be simplified and the device can be easily manufactured. Further, a positioning hole formed in a connection portion between each electrode lead semiconductor chip of the first embodiment and a positioning protrusion formed near the long side of the bottom surface is not required, and can be easily formed. A semiconductor light emitting device that can be used.

A method for manufacturing the above semiconductor light emitting device will be described. First, as shown in FIG. 6A, an N-type semiconductor layer 7 made of N-type GaN by, for example, epitaxial growth on a transparent sapphire wafer 6 that is light-transmissive, for example.
Is formed, and a P-type semiconductor layer 8 of P-type GaN is formed thereon. The upper layer of the P-type semiconductor layer 8 is made of P
The electrode 9 and the P-electrode projection 16 are formed, while the N-electrode 10 and the N-electrode projection 17 made of, for example, gold are also formed on the upper layer of the N-type semiconductor layer 7.

Next, as shown in FIG. 6B, the P electrode 9, the P electrode convex portion 16, the N electrode 10 and the N electrode convex portion 17 are formed.
The anisotropic conductive layer 18 is formed by coating an anisotropic conductive film or applying an anisotropic conductive material thereon.

Next, as shown in FIG. 6C, one wafer is divided into individual semiconductor chips (C1, C2 in the drawing) by a dicing process. In the subsequent steps, each semiconductor chip is pressed against the pair of electrode leads from the side of the electrode protrusions to crush the anisotropic conductive layer 18 and fix the semiconductor chip by the adhesive force of the anisotropic conductive layer 18. At this time, the P electrode protrusion 1
6 and the P electrode lead 1, or the N electrode projection 17
The anisotropic conductive layer 18 between the anisotropic conductive layer 18 and the N electrode lead 2 is thinly crushed.
Electrical continuity is provided between the electrode projection 16 and the P electrode lead 1 and between the N electrode projection 17 and the N electrode lead 2. Next, for example, the whole is sealed with a sealing resin to obtain a semiconductor light emitting element.

Next, another manufacturing method different from the above manufacturing method will be described. First, steps up to FIG. 7A are the same as in the above method. Next, as shown in FIG. 7B, a lattice-shaped slit S is formed at each division position in each semiconductor chip of the wafer. At this time, the slit is partially inserted into the wafer and stopped so as not to be completely divided into individual semiconductor chips.

Next, as shown in FIG. 7C, the P electrode 9, the P electrode convex portion 16, the N electrode 10 and the N electrode convex portion 17 are formed.
An anisotropic conductive material is applied thereon by, for example, a roll transfer printing method to form an anisotropic conductive layer 18. At this time,
An anisotropic conductive layer is not formed in the slit portion S.

Next, as shown in FIG. 7D, an expanded film (not shown) is attached to the wafer, and the wafer is divided so as to expand the slit portion S. One wafer is divided into individual semiconductor chips (D1, D1 in the drawing). D2). In the subsequent steps, for example, each semiconductor chip is pressed against a pair of electrode leads from the side of the electrode protrusions to form a gap between the P electrode protrusion 16 and the P electrode lead 1 or N The electrode projection 17 and the N-electrode lead 2 are fixed so as to be conductive by the conductive particles in the anisotropic conductive layer 18, and the whole is sealed with a sealing resin to obtain a semiconductor light emitting element. .

According to the method for manufacturing a semiconductor light emitting device of the present embodiment, the semiconductor chip and the electrode leads are connected by the anisotropic conductive layer, so that a wire or a half that blocks light from the light emitting layer as in the prior art is used. Since there is no transparent thin-film electrode and the thickness of the P electrode and the N electrode can be made sufficiently thick, the light reflectance at the electrode portion is increased, and a semiconductor light emitting device with improved light extraction efficiency is manufactured. can do. Since the necessity of increasing the light reflectance on the bottom surface of the concave portion of the electrode lead is reduced, the concave bottom surface does not have to be a mirror surface, so that the manufacturing cost of the electrode lead can be reduced. In addition, since the anisotropic conductive layer is formed before dividing the wafer into individual semiconductor chips, manufacturing is easy, and connection, positioning, and fixing of the semiconductor chips to the electrode leads can be performed at the same time. The process can be simplified and easily manufactured.

Third Embodiment FIG. 8 is a schematic diagram of a display device according to the third embodiment . This is a display device in which a plurality of the semiconductor light emitting devices according to the first embodiment or the second embodiment are arranged in a matrix. In the drawing, three semiconductor light-emitting elements (LED1, LED
2, LED 3). The horizontal direction of the display screen when the display screen is used as a display device placed vertically is indicated by a direction H, and the vertical direction is indicated by a direction V. The positional relationship between the P electrode 12 and the N electrode 13 of each semiconductor light emitting element is aligned in one direction. Here, the P electrodes 12 of the respective semiconductor light emitting elements are arranged so as to be on the upper side (u side in the drawing). The light emission centers EC of the plurality of semiconductor light emitting elements 3 are aligned on the upper side. Further, the pair of electrode leads 1 and 2 are aligned so that the divided surfaces thereof are substantially in the horizontal direction (the H direction in the drawing). This makes it possible to increase the viewing angle in the lower direction than the upper direction of the screen of the display device and in the horizontal direction than in the vertical direction. Since each semiconductor light emitting element has high luminance, it is possible to provide a display device which requires outdoor high luminance.

The present invention is not limited to the above embodiment. For example, the substrate of the semiconductor chip is not limited to a sapphire substrate, and any transparent substrate can be used. Further, another semiconductor such as GaN can be used for the semiconductor layer. The P electrode and the N electrode are not particularly limited, but are preferably made of a material that can reflect light by increasing the film thickness. In addition, various changes can be made without departing from the spirit of the present invention.

[0053]

According to the semiconductor light emitting device of the present invention, it is possible to provide a semiconductor light emitting device capable of effectively extracting light generated from the light emitting layer.

According to the method for manufacturing a semiconductor light emitting device of the present invention, the semiconductor light emitting device of the present invention can be easily manufactured, and a semiconductor light emitting device with improved light extraction efficiency can be manufactured.

Further, according to the display device of the present invention, there is provided a display device formed by arranging a plurality of the semiconductor light emitting elements of the present invention in a matrix and capable of effectively extracting light generated from the light emitting layer. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a semiconductor light emitting device according to a first embodiment.

FIG. 2A is an enlarged plan view of a main part of the semiconductor light emitting device according to the first embodiment, and FIG. 2B is a plan view of FIG.
It is sectional drawing in AA 'of (a).

FIG. 3 is a sectional view further enlarging the vicinity of the semiconductor chip of FIG. 2 (b).

FIG. 4A is a plan view of a main part of a semiconductor light emitting device according to a second embodiment, and FIG. 4B is a cross-sectional view taken along line AA ′ of FIG. 4A.

FIG. 5 is a cross-sectional view further enlarging the vicinity of the semiconductor chip of FIG. 4 (b).

FIGS. 6A and 6B are cross-sectional views illustrating a manufacturing process of a method for manufacturing a semiconductor light emitting device according to a second embodiment, in which FIG. 6A illustrates up to the process of forming an N-electrode projection and a P-electrode projection, and FIG. Shows up to the step of forming an anisotropic conductive layer, and (c) shows up to the dicing step.

FIGS. 7A and 7B are cross-sectional views illustrating a manufacturing process of a method for manufacturing a semiconductor light emitting device according to a second embodiment, in which FIG. 7A illustrates up to a process of forming an N-electrode projection and a P-electrode projection, and FIG. 5A shows a process of forming a lattice-shaped slit in a wafer, FIG. 5C shows a process of forming an anisotropic conductive layer, and FIG. 5D shows a process of dividing an individual semiconductor chip.

FIG. 8 is a schematic diagram of a display device according to a third embodiment.

FIG. 9 is a schematic diagram of a semiconductor device according to a conventional example.

FIG. 10A is an enlarged view of a main part of a semiconductor device according to a conventional example, and FIG. 10B is a sectional view taken along line B-B of FIG.
It is sectional drawing in B '.

FIG. 11 is a cross-sectional view further enlarging the vicinity of the semiconductor chip of FIG. 10 (b).

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... P electrode lead, 2 ... N electrode lead, 3 ... Semiconductor chip, 4 ... Seal resin (lens), 5 ... Semiconductor chip recess side wall surface, 5 '... Semiconductor chip recess bottom surface, 6 ... Sapphire substrate, 7 ... N-type semiconductor layer, 8 ... P-type semiconductor layer, 9 ... P
Electrode, 10 ... N electrode, 11 ... Protective insulating film, 12, 13 ...
Conductive layer, 14: underfill sealant, 15: projection for positioning, 16: convex portion of P electrode, 17: convex portion of N electrode, 18 ...
Anisotropic conductive layer, H1, H2: positioning hole, J: PN junction, E: light emitting area, C1, C2, D1, D2: semiconductor chip, S: slit, LED1 to LED3: semiconductor light emitting element, 21 ... N electrode lead, 22 ... P electrode lead, 2
3 ... semiconductor chip, 24 ... sealing resin (lens), 25,
26: Wire, 27: Side wall surface of recess for semiconductor chip, 2
7 ′: bottom surface of concave portion for semiconductor chip, 28: sapphire substrate, 29: N-type semiconductor layer, 30: N electrode, 31: active layer, 32: P-type semiconductor layer, 33: first P electrode, 34: second P electrode, 35: protective insulating film, 36: adhesive layer.

Claims (19)

[Claims] A light-emitting layer formed by laminating a p-type semiconductor layer and an n-type semiconductor layer and emitting light by applying a predetermined voltage between the p-type semiconductor layer and the n-type semiconductor layer; A semiconductor chip having a P-electrode and an N-electrode connected to the P-type semiconductor layer and the N-type semiconductor layer, respectively; and a recess for the semiconductor chip, the surface of which is a reflection surface of light emitted from the light emitting layer. A pair of electrode leads divided so as to be insulated from each other, and the pair of electrode leads and the P electrode or the N electrode to connect the pair of electrode leads to the P electrode or the N electrode. A semiconductor light-emitting device having a conductive layer disposed between them. 2. The semiconductor light emitting device according to claim 1, wherein said light emitting layer is formed on a light transmitting insulating substrate. 3. The semiconductor light emitting device according to claim 1, wherein said pair of electrode leads have a substantially plane-symmetric shape. 4. The semiconductor light emitting device according to claim 1, wherein said pair of electrode leads are divided at diagonal positions of said semiconductor chip. 5. The semiconductor device according to claim 1, wherein the shape of the bottom surface of the concave portion of the pair of electrode leads is substantially similar to the shape of the semiconductor chip.
The semiconductor light-emitting device according to claim 1. 6. The semiconductor chip has a substantially square shape, the bottom shape of the concave portion of the one electrode lead has a triangular shape, and the angle of the apex angle of the triangle is the angle formed by the apex angle of the semiconductor chip. 6. The semiconductor light emitting device according to claim 5, which is the same as described above. 7. The semiconductor light emitting device according to claim 1, wherein a depth of said concave portion of said electrode lead is substantially equal to a thickness of said semiconductor chip. 8. The semiconductor light emitting device according to claim 1, wherein said concave surface of said electrode lead is substantially formed as a mirror surface for reflecting light emitted from said light emitting layer. 9. The semiconductor light emitting device according to claim 1, wherein the side wall surface of the concave surface of the electrode lead has a tapered shape that becomes wider toward the opening. 10. A positioning hole for the semiconductor chip is formed in a bottom surface of the concave portion of the electrode lead, and the hole is filled with a conductor connected to the P electrode or the N electrode. 2. The semiconductor light emitting device according to 1. 11. The semiconductor light emitting device according to claim 1, wherein the P electrode and the N electrode are covered with an insulator having poor wettability to the conductor except for a region connected to the electrode lead by a conductor. 12. At least three protrusions for positioning the bottom surface of the recess and the bonding surface of the P-type semiconductor layer and the N-type semiconductor layer of the semiconductor chip substantially in parallel are provided on the bottom surface of the recess of the pair of electrode leads. 2. The semiconductor light emitting device according to claim 1, wherein the semiconductor light emitting device is formed. 13. The semiconductor light emitting device according to claim 1, wherein said conductive layer is an anisotropic conductive material. 14. A bonded body of an N-type semiconductor layer and a P-type semiconductor layer on a light-transmitting insulating wafer, and a predetermined voltage is applied between the P-type semiconductor layer and the N-type semiconductor layer. Forming a light-emitting layer that emits light, forming a P-electrode connected to the P-type semiconductor layer, forming an N-electrode connected to the N-type semiconductor layer, Forming an anisotropic conductive layer by covering the N-electrode, dicing the wafer into individual semiconductor chips, and forming a surface on which a light-reflecting surface of the light-emitting layer is reflected. The pair of electrode leads and the P electrode or the N electrode are connected via the anisotropic conductive layer to a pair of electrode leads having a recess for a semiconductor chip and divided so as to be insulated from each other. So that the semiconductor chip is fixed The method of manufacturing a semiconductor light emitting device and a that step. 15. A joined body of an N-type semiconductor layer and a P-type semiconductor layer on a light-transmitting insulating wafer, and a predetermined voltage is applied between the P-type semiconductor layer and the N-type semiconductor layer. Forming a light emitting layer that emits light, forming a P electrode connected to the P-type semiconductor layer, forming an N electrode connected to the N-type semiconductor layer, and forming a lattice on the wafer. Forming an anisotropic conductive layer by covering the P-electrode and the N-electrode; expanding the slit portion of the wafer to divide the wafer into individual semiconductor chips; The pair of electrode leads having the concave portion for the semiconductor chip serving as a reflection surface of light emitted by the light emitting layer and being divided so as to be insulated from each other, the pair of electrode leads and the P electrode or the P electrode N electrode is anisotropic conductive To connect through a method of manufacturing a semiconductor light emitting device and a step of fixing the semiconductor chip. 16. A light emitting layer which is formed by laminating a P-type semiconductor layer and an N-type semiconductor layer, and emits light by applying a predetermined voltage between the P-type semiconductor layer and the N-type semiconductor layer. A semiconductor chip having a P-electrode and an N-electrode connected to the P-type semiconductor layer and the N-type semiconductor layer, respectively; and a recess for the semiconductor chip, the surface of which is a reflection surface of light emitted from the light emitting layer. A pair of electrode leads divided so as to be insulated from each other, and the pair of electrode leads and the P electrode or the N electrode to connect the pair of electrode leads to the P electrode or the N electrode. A display device in which a plurality of semiconductor light-emitting elements having a conductive layer disposed therebetween are arranged in a matrix. 17. The semiconductor device according to claim 16, wherein the P electrodes and the N electrodes of the plurality of semiconductor light emitting elements are aligned in one direction.
The display device according to the above. 18. The display device according to claim 16, wherein the light emission centers of said plurality of semiconductor light emitting elements are aligned upward. 19. The display device according to claim 16, wherein the division surfaces of the pair of electrode leads are aligned so as to be substantially horizontal.