JPH07183571A - Semiconductor light-emitting device - Google Patents

Abstract

PURPOSE:To obtain the semiconductor light-emitting device which can realize a high-quality printing operation or the like without lowering an MTF by a method wherein, when the semiconductor light-emitting device is used as a light source for an optical. printer or the like, the stray light of light from the edge of an edge-luminous light-emitting diode array is reduced as fas as possible. CONSTITUTION:In a semiconductor light-emitting device, a plurality of edge- luminous light-emitting diodes are arranged on the same substrate 301 in one or more rowws in a direction parallel to a light-radiating face, and an edge- luminous light-emitting diode array 302 in which the individual light-emitting diodes have been isolated by isolation grooves is formed. In the semiconductor light-emitting device, a light-shielding member 304 which is used to control the directivity of radiated light from the edge of every light-emitting diode is formed on a discrete electrode 305 for every light-emitting diode.

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 used as a writing light source for an optical printer or a digital copying machine.

[0002]

2. Description of the Related Art A semiconductor light emitting device using a light emitting diode array has been studied for the purpose of application to a light source of an optical printer or the like adopting an electrophotographic printing method. Here, in an optical printer, a light emitting diode array for a light source is composed of a self-emission type array element, and the light emitting diode array is caused to emit light in accordance with an image signal, and the light is imaged on a surface of a photoconductor by an equal magnification imaging element. By doing so, an electrostatic latent image is formed, and the electrostatic latent image is developed with a developer and then transferred to a transfer paper or the like to perform printing by electrophotography.

Since the light emitting diode array has no moving parts and has a small number of constituent parts, when used in a print head of such an optical printer, the print head can be downsized. In addition, the LED array is self-luminous and has a high extinction ratio and good contrast can be obtained.Furthermore, by connecting the LED array chip, it is possible to support longer lengths, and the higher output of the light emitting diode enables higher speed. It is possible to obtain various benefits such as being able to deal with. As the light emitting diode array, there are a surface emitting light emitting diode array in which a large number of light emitting portions such as squares are arranged in a predetermined direction in a plane parallel to the substrate surface, and a plurality of light outputs arranged in a predetermined direction from an end face perpendicular to the substrate surface. There are edge emitting type light emitting diode arrays and the like obtained.

First, as a basic structure of a surface emitting type light emitting diode array, for example, a structure as shown in FIG. 5 has been reported (Proceedings of the National Conference of the Institute of Electronics and Communication Engineers, Communications Division, 1980, No. 1-211). See page). In such a surface emitting light emitting diode array, in many cases, in order to make the intensity of the light output obtained from the light emitting portion 501 uniform within the light emitting surface, electrodes 511 are formed at both ends or around the light emitting portion. There is. In this surface-emitting light-emitting diode array, since the light emitting section 501 from which the light output is taken out and the electrode 511 are on the same plane, the width required per unit element is the width of the light emitting section 501 and the width of the electrode 511, and the element. It is the total width of the separation areas. For example, 600 dpi (dots
It is extremely difficult to form the light emitting portion 501 with high density such as per inch or more.

Next, as an edge emitting type light emitting diode array, for example, one as shown in FIG. 6 is disclosed in Japanese Patent Laid-Open No. 60-323.
No. 73 publication. In this edge emitting type light emitting diode array, a plurality of light emitting portions 601 are formed in a laminated structure on a substrate 635, and these light emitting portions 601 are formed.
Are electrically and spatially separated by a separation groove 602 formed in a plane parallel to the surface of the substrate 635 in a direction perpendicular to the end face thereof.

In such an edge emitting type light emitting diode array, the light emitting portion 601 and the electrode 61 from which the light output is taken out.
1, 612 do not exist on the same surface, and the width required for each unit element is the sum of the width of the light emitting portion 601 and the width of the element isolation region. For example, the high density of the light emitting portion 601 is 600 dpi or more. Formation is possible in principle. Therefore, it can be said that the edge emitting type light emitting diode array is suitable as the light emitting diode array used in the high density optical printer.

By the way, in order to realize high speed driving of a light source for a high density optical printer, a semiconductor light emitting device is known in which a plurality of light emitting diode arrays are arranged adjacent to each other in a column direction and dividedly driven. Of the semiconductor light emitting devices in which a plurality of light emitting diode arrays are arranged adjacent to each other in the column direction, the edge emitting type light emitting diode array is used as a light emitting end face by cleavage as shown in FIG. In addition to the structure in which 625 is formed, FIG. 7 shows a structure in which a light emitting end face is formed by using an etching technique and a portion apart from the light emitting end face is cut out to form a light emitting diode array by dicing or scribing. In this semiconductor light emitting device, a plurality of light emitting portions 701 are formed in a laminated structure on a substrate 742, and these light emitting portions 701 are in a plane parallel to the surface of the substrate 742 and in a direction perpendicular to the end face thereof. It is electrically and spatially separated by the formed separation groove 702, and the light emitting end face is formed at a position apart from the light emitting end face, and a terrace 741 is formed in front of the light emitting end face. Here, the terrace taken to prevent damage due to the scribe of the light emitting end surface is called a terrace.

[0008]

[Problems to be Solved by the Invention]
When a semiconductor light emitting device having a structure as shown in FIG. 8 is mounted on a base substrate and is used as a light source for an optical printer, FIG.
As shown in, the relationship between the light emitting portion of the light emitting diode 801 and the image forming point on the surface of the photosensitive drum 803 is that the light from the light emitting diode 801 is imaged on the surface of the photosensitive drum 803 via the equal-magnification image forming element 802. However, in such an optical system, the lens angle Θ (= arctan (φ / 2s):
φ is the effective aperture of the lens, and s is the object distance). That is, the numerical aperture (NA = ns) of the unity-magnification imaging element 802.
Since in Θ: n is the refractive index of the medium, the MTF (spatial frequency of the lens) and the like are taken into consideration. The light utilization efficiency decreases due to the light that cannot be incident on the child 802. Further, the light that could not be incident on the same-magnification imaging element 802 becomes stray light, which lowers the MTF.

Under such circumstances, efforts have been made to reduce the angle θ of the light beam as one means for solving the above problems. Generally, in an edge-emitting LED array, the light emission from the light emitting end face to the back does not contribute much to the light output, but rather the light emission near the light emitting end face mainly contributes to the light output. It is known that the angle θ of the light flux in the direction perpendicular to is smaller than that of the surface emitting light emitting diode array.

In the experiments conducted by the inventor of the present invention, the angle θ of the light beam
Is 2θ≈120 ° in the surface emitting light emitting diode array, whereas it is 2 in the edge emitting light emitting diode array.
It is in the range of θ = 30 ° to 100 ° (in the case of the double heterojunction type), and the inventor of the present invention confirmed that it is possible to produce an element having a desired luminous flux angle in this range. is doing. However, when the angle of the light flux from the end face of the light emitting diode 801 is larger than the numerical aperture of the equal-magnification imaging element 802, not only the light utilization rate decreases as described above, but also the light from the end face of the light emitting diode 801 decreases. Will enter as stray light at a position other than the desired position of the unity-magnification imaging element 802, and the MTF will be lowered.

The present invention solves the above drawbacks and minimizes stray light from the end faces of the edge emitting type light emitting diode array when used as a light source for an optical printer or the like. An object of the present invention is to provide a semiconductor light emitting device that can realize quality printing and the like.

[0012]

In order to achieve the above object, the invention according to claim 1 arranges a plurality of edge emitting light emitting diodes on the same substrate in a direction parallel to the light emitting surface in one or more rows. In a semiconductor light emitting device having an edge emitting type light emitting diode array in which each light emitting diode is electrically and spatially separated by a separation groove, a direction of light emitted from the end face of the light emitting diode is directed onto an individual electrode of the light emitting diode. A light shielding member for controlling the property is provided.

According to a second aspect of the present invention, a plurality of edge emitting type light emitting diodes are arranged on the same base substrate in a direction parallel to the light emitting surface in a line or more, and the light emitting diodes are electrically separated by a separating groove. In a semiconductor light emitting device having an edge emitting light emitting diode array that is physically and spatially separated,
The individual electrode side of the light emitting diode is mounted by junction down on the base substrate to be a heat sink,
The base substrate controls the directivity of light emitted from the end face of the light emitting diode.

The invention according to claim 3 is the invention according to claim 1 or 2.
In the semiconductor light emitting device described above, the edge emitting type light emitting diodes each include a double heterojunction.

The invention according to claim 4 is the invention according to claim 1 or 2.
In the semiconductor light emitting device described above, the edge emitting light emitting diodes each include a single heterojunction, a homojunction, or a diffusion P-N junction.

The invention according to claim 5 is the invention according to claim 1 or 2.
In the semiconductor light emitting device described above, the base substrate and the edge emitting light emitting diode are reflected in a region that can be a slit for emitted light so as to suppress reflection with respect to a wavelength of light emitted from the edge emitting light emitting diode. A protective film is provided.

According to a sixth aspect of the present invention, in the semiconductor light emitting device according to the second aspect, the individual electrode side of the light emitting diode is mounted on the base substrate by surface mounting by bumps.

According to a seventh aspect of the present invention, in the semiconductor light emitting device according to the second aspect, the individual electrode side of the light emitting diode is surface-mounted on the base substrate by an anisotropic conductive adhesive or an anisotropic conductive film. It is mounted.

[0019]

According to the present invention, the directivity of the light emitted from the end face of the light emitting diode is controlled by the light shielding member or the base substrate.

According to a fifth aspect of the present invention, in the semiconductor light emitting device according to the first or second aspect, the region which can serve as a slit for the emitted light of the base substrate and the edge emitting light emitting diode is emitted from the edge emitting light emitting diode. Light is less likely to be reflected by the antireflection film. Therefore, stray light due to reflected light or scattered light from the area that can be a slit is reduced, and variations and instability of the light emission pattern (far field image) are removed.

According to a sixth aspect of the present invention, in the semiconductor light emitting device according to the second aspect, the individual electrode side of the light emitting diode is mounted on the base substrate by surface mounting with bumps, so that the light emitting diode array is miniaturized and miniaturized. Is easy to implement.

According to a seventh aspect of the invention, in the semiconductor light emitting device according to the second aspect, the individual electrode side of the light emitting diode is mounted on the base substrate by surface mounting with an anisotropic conductive adhesive or an anisotropic conductive film. This facilitates high-density miniaturization of the light emitting diode array in terms of mounting.

[0023]

The embodiment of the present invention is one in which a plurality of edge emitting type light emitting diodes are arranged in one or more rows on the same substrate, and the direction of arrangement of the light emitting diodes is a light emitting surface, that is, a surface from which light is to be extracted. It is parallel to the direction. The plurality of light emitting diodes are electrically and spatially separated from each other by the separation groove. Each edge emitting LED may be configured to include a double heterojunction,
It may be configured to include a single heterojunction, a homojunction, or a P-N junction by diffusion. In the double heterojunction, by controlling the refractive index of the cladding layer and active layer, the thickness of the active layer, etc., the angle of the light flux from the light emitting surface can be controlled to be smaller than in other junctions, and the light utilization rate can be increased. You can

As the light emitting diode structure having the double heterojunction, "a first conductivity type GaA is formed on a common first conductivity type (N-type or P-type) GaAs substrate.
s buffer layer, first conductivity type Al _x Ga _1-x As first clad layer, and light emitting layer Al _y Ga _1-y A
s (x> y) active layer, second conductivity type (P type or N
Type) second cladding layer made of Al _x Ga _1-x As, second
A structure having a cap layer made of conductivity type GaAs "is possible.

In such a light emitting diode structure, the separation groove is formed at a depth from the cap layer side to at least the first cladding layer. In order to control the directivity of light emission from the end face of such an edge-emitting LED array, each individual electrode is electrically connected to the individual electrode formed on the upper part of each LED of the LED array. A light-shielding plate having at least an insulating surface so that it does not come into contact with the junction junction up, that is, the semiconductor substrate side may be fixed on a base substrate that is a heat sink, or it may be formed on each light emitting diode of the light emitting diode array. A junction down structure using surface mounting may be used in which the formed individual electrodes are fixed to the side of the base substrate that is the heat sink.

In order to form a junction down structure using surface mounting, it is necessary to mount the light emitting diode array on the base substrate so that the individual electrodes formed above each light emitting diode do not come into electrical contact with each other. Don't There are the following two methods for implementing the method. First
In this method, first, on the base substrate, which is a heat sink on which the light emitting diode array is fixedly mounted, a metal for connecting each light emitting diode from the driver for controlling each light emitting diode to operate individually is formed. Bumps are formed by a plating method through an insulating film having a window to electrically connect the individual electrodes of the diode. The metal and the individual electrodes of each light emitting diode are electrically connected only through the bumps, and the other regions are electrically disconnected by the insulating film. As described above, the first method of mounting the light emitting diode on the base substrate by using the bump may be used.

In the second method, a metal for connecting each light emitting diode to a driver for controlling each light emitting diode to individually operate is formed on a base substrate which is a heat sink on which the light emitting diode array is fixedly mounted. The light emitting diode array is fixed with an anisotropic conductive adhesive through an insulating film having a window opened to electrically connect only the metal and the individual electrode. The anisotropic conductive adhesive is made by dispersing conductive powder in a hot metal type or thermosetting type resin, so that the conductive powder inside the anisotropic conductive adhesive does not come into contact with each other. Therefore, the individual electrodes of the adjacent light emitting diodes are not electrically connected to each other, and only the individual electrodes that are in contact with each other and the metal connected to the corresponding driver are electrically connected.
As described above, the second method of mounting the light emitting diode on the base substrate by using the anisotropic conductive adhesive may be used. The anisotropic conductive adhesive may be formed on the anisotropic conductive film.

As described above, a light shielding plate is provided to control the directivity of light emission from the end surface of the edge emitting type light emitting diode array, or surface mounting using bumps or anisotropic conductive adhesive is performed by junction down. By rubbing, the angle of the light flux can be controlled to be smaller than the numerical aperture of the equal-magnification imaging element, and the light from the light-emitting diode enters as stray light at a position other than the position of the desired multiple-magnification imaging element to lower the MTF. Things will be less. Furthermore, by providing an antireflection film so as to suppress the reflection of the wavelength of the light emitted from the light emitting diode which can be a slit for the light emitted from the end face of the light emitting diode array, the light emitted from the end face of the light emitting diode array is provided. It is possible to reduce stray light due to reflected light or scattered light from a region that can be a slit, and to eliminate variations and instability in the light emission pattern (far-field image), and further increase the MTF.

Next, the structure and manufacturing process of the edge emitting light emitting diode array used in the embodiments of the present invention will be described. As shown in FIGS. 2A and 2B, for example, N
MBE (Molecular B)
eam Epitaxy method, LPE (Liquid Phase Epitaxy)
Method, chloride VPE (Vapor Phase Epitaxy) method, or MOCVD (Metal Organic Chemical Vapor)
Buffer layer 101 made of n-GaAs, a clad layer 102 made of n-Al _0.4 Ga _0.6 As, and a light emitting layer of Al _0.2 Ga _0.8 A by using a crystal growth method such as a deposition method.
An active layer 103 made of s, a cladding layer 104 made of p-Al _0.4 Ga _0.6 As, and a cap layer 105 made of p-GaAs are sequentially laminated. These layers contain double heterojunctions.

Next, as shown in FIGS. 2C and 2D, p-
An etching mask 106 is formed on the cap layer 105 made of GaAs using a photolithography process. As the etching mask, a resist (positive type, negative type), a dielectric film such as SiO ₂ or a metal thin film such as Cr can be used. Next, FIG. 2 (e)
As shown in (f), a fine width separation groove 107 reaching at least the cladding layer 102 made of n-Al _0.4 Ga _0.6 As and a light emitting end surface 108 for extracting light emitted from the active layer 103 by a dry etching method using chlorine gas. To form. At this time, at the same time, the shape of the substrate in front of the light emitting end face 108 of the light emitting diode is changed to the terrace 1 shown in FIG.
It is formed into a 09 shape. A wet etching method may be used instead of dry etching. Further, when the cleavage method is used, the terrace 109 may not be formed.

Next, as shown in FIGS. 2 (g) and (h), EB
An insulating film 110 made of SiO ₂ , SiN, or the like is formed by vapor deposition or plasma CVD, and the insulating film 110 is further subjected to photolithography and etching processes to form a cap layer 105 and a p-layer.
A window 111 is opened so that the side ohmic electrode can be electrically contacted.

Next, as shown in FIGS. 1I and 1J, Au-Zn / Au or the like is vapor-deposited as the p-side ohmic electrode 112 on the window portion 111 of the insulating film 110, and then the cap layer 105 is formed on the cap layer 105 by the lift-off method. Align the position and cap layer 10
A p-side ohmic electrode 112 is formed on the upper part of the layer 5. Finally, on the back surface side of the substrate 100 made of n-type GaAs,
That is, the n-type ohmic electrode 113 is formed by vapor deposition on the surface on which no crystal growth has occurred.

The laminated structure and the manufacturing process of the light emitting diode array described above are merely examples, and the laminated structure and the manufacturing process may be different from those described above as long as it is an edge emitting type light emitting diode array. Further, as the junction method for controlling the light emitting layer of the light emitting diode, a single hetero junction, a homo junction, or a P-N junction by diffusion may be used other than the above-mentioned diable hetero junction.

FIG. 1 shows a first embodiment of the present invention. The first embodiment shows an embodiment in which a light shielding plate is used to control the directivity of light emitted from the end surface of the edge emitting type light emitting diode array. In the first embodiment, as shown in FIG. 1A, the edge emitting light emitting diode arrays 302-1 to 302-n are junction-up to a base substrate 301 having good thermal conductivity, that is, the edge emitting light emitting diode array. 302
-1 to 302-n are die-bonded in a line perpendicular to the light emitting direction 303 with the substrate side thereof as the base substrate 301 side, to form an edge emitting light emitting diode array 302-1.
A light-shielding plate 304 for controlling the directivity of the luminous flux is mounted on the individual electrodes of the respective light-emitting diodes No. 302-n.

FIG. 1B is a sectional view taken along the line AA of FIG. 1A and shows an edge emitting type light emitting diode array 302-1.
302-n is as described above, and the common electrode 306
And the substrate 100, the buffer layer 101, and the cladding layer 10.
2 and the N-side semiconductor 343 and the active layer 342 (10
3), a P-side semiconductor 341 including the clad layer 104 and the cap layer 105, and an individual electrode 305 (112).

This edge emitting type light emitting diode array 30
2-1 to 302-n are terraces 311 in front of the light emitting end face of the light emitting diode formed at the same time as the element isolation and the light shielding plate from the light emitting end face in the light extraction direction in the steps shown in FIGS. Control the length of the protrusion of 304,
The light beam 351 from the light emitting end surface of the light emitting diode is made smaller than the aperture diameter of the equal-magnification imaging element in front of the light emitting end surface of the light emitting diode.

Here, the light shield plate 304 is provided on the individual electrode 305, and at least the light shield plate 3 is provided in order to prevent the individual electrodes of the respective light emitting diodes from electrically contacting each other.
The surface of 04 is made of an insulating material. That is, the light emitted from the light emitting end surface of the light emitting diode is blocked by the terrace 311 and the light blocking plate 304 in front of the light emitting end surface of the light emitting diode, which can serve as a slit, of light having a component larger than the aperture diameter of the equal-magnification imaging element. It is possible to reduce unnecessary light as much as possible. Further, an antireflection film 312 is provided on the terrace 311 and the light shielding plate 304 in front of the light emitting end surface of the light emitting diode that can be the slit, and the light emitted from the light emitting end surface of the light emitting diode is reflected from the area that can be the slit. Stray light due to light or scattered light is reduced by the antireflection film 312, and variations and instability of the light emission pattern (far field image) are removed.

Further, the base substrate 301 is formed with metal 331, 332 electrically connected to a driver for operating the light emitting diode arrays 302-1 to 302-n through an insulating layer 335, and each light emission is performed. The individual electrode 305 of the diode is connected to each metal 332 by wire bonding 360, and the common electrode 306 is connected to the metal 33.
Connected to 1. Therefore, the current flowing in each light emitting diode flows from the driver to the metal 332, the wire bonding 360, the individual electrode 305, the P-side semiconductor 341, the active layer 342, the N-side semiconductor 343, the common electrode 306, and further from the metal 331 to the driver. .

FIG. 3 shows a second embodiment of the present invention. In the second embodiment, the edge emitting light emitting diode array is mounted on the base substrate by bumps to control the directivity of light emitted from the edge of the edge emitting light emitting diode when the element is separated from the base substrate. This is an example in the case of performing on the terrace in front of the light emitting end face. In the second embodiment, the light emitting diode arrays 302-1 to 30-2 are mounted on the base substrate 301 which has good thermal conductivity and at least the surface of which is insulated by the insulating layer 335.
The bumps 321 are formed by plating at positions matching the individual electrodes of the 2-n light emitting diodes. This bump 3
21 is a metal such as Au. Insulation layer 335 is bump 3
A window for electrically connecting the bump 321 and the metal 331 is provided at a position where 21 is formed.

The base substrate 301 has metal 331 and 332 electrically connected to a driver for operating the edge emitting light emitting diode arrays 302-1 to 302-n via an insulating layer 335. The light emitting type light emitting diode arrays 302-1 to 302-n are as described above. Bumps 321 formed on the base substrate 301
The edge emitting type light emitting diode arrays 302-1 to 302-n are subjected to junction down by aligning the position of each light emitting diode, that is, the edge emitting type light emitting diode arrays 302-1 to 302-n are made to emit light. The individual electrode 305 of the diode is connected to the bump 3 on the base substrate 301.
On the 21st side, they are mounted in a line so as to form a line in a direction perpendicular to the light emission direction 303. The common electrode 306 of each light emitting diode is connected to the metal 332 by the wire bonding 360.
Connected to.

Here, the currents flowing in the respective light emitting diodes are respectively from the driver to the metal 331 on the base substrate 301,
It flows to the bump 321, the individual electrode 305, the P-side semiconductor 341, the active layer 342, the N-side semiconductor 343, the common electrode 306, and further to the driver through the wire bonding 360 and the metal 331.

Edge emitting type light emitting diode array 302-
1 to 302-n are the steps shown in FIGS. 1E and 1F, from the terrace 311 in front of the light emitting end face of the light emitting diode formed at the same time as the element isolation and from the light emitting end face of the base substrate 301 in the light extraction direction. The length of the protruding portion is controlled so that the light flux 351 from the light emitting end surface of the light emitting diode is smaller than the aperture diameter of the unity-magnification imaging element in front of the light emitting end surface of the light emitting diode. That is, the light emitted from the light emitting end surface of the light emitting diode has a component larger than the aperture diameter of the equal-magnification imaging element due to the terrace 311 in front of the light emitting end surface of the light emitting diode that can be a slit and the protruding portion from the base substrate 301. Light is blocked and unnecessary light is reduced as much as possible.

Further, an antireflection film 312 is provided on the terrace 311 in front of the light emitting end face which can be the slit and the projecting portion from the base substrate 301, and can serve as a slit for the light emitted from the light emitting end face of the light emitting diode. Stray light due to reflected light or scattered light from the area is applied to the antireflection film 312.
Variation in the light emission pattern (far-field image) due to
Instability is eliminated.

In the third embodiment of the present invention, a similar effect is obtained by using the anisotropic conductive adhesive in place of the bump 321 in the second embodiment. The anisotropic conductive adhesive used here is one in which conductive powder is dispersed in a hot mel type or thermosetting type resin, and there are a film type and a paste type. Here, the anisotropic conductive adhesive may be used in the form of a film or a paste, and the film-like one is called an anisotropic conductive film.

FIG. 4 shows the base substrate 3 in the above embodiment.
Metal 3 that is electrically connected to the driver on the surface of 01
31 schematically shows how the light emitting diode 31 and the individual electrode 305 of each light emitting diode are connected. 4A and 4B show the case of the second embodiment, and FIGS. 4C and 4D show the anisotropic conductive adhesive 3
This is the case of the third embodiment using No. 25. In the third embodiment using the anisotropic conductive adhesive, the second bump using the bump 321 is used.
Similar to the embodiment, the separation groove 307 is formed in the steps of FIGS.
A terrace 311 formed at the same time, which is in front of the light emitting end face of the light emitting diode, and the base substrate 3 in the light extraction direction.
The effect of controlling the length of the protruding portion of 01 from the light emitting end surface of the light emitting diode to make the light flux 351 from the light emitting end surface of the light emitting diode smaller than the aperture diameter of the equal-magnification imaging element in front of the light emitting end surface of the light emitting diode. It is obtained as in the second embodiment.

In the third embodiment formed using the anisotropic conductive adhesive 325, the light emitting diode arrays 302-1 to 302-n and the base substrate 301 are more closely attached than in the second embodiment using the bump 321. Therefore, the heat generated in the light emitting diode is easily radiated by the base substrate 301 having good thermal conductivity, and the light emitting efficiency of the light emitting diode can be improved. Increasing the luminous efficiency of the light emitting diodes by using the bumps 321 is achieved by using the base substrate 301 and the light emitting diode arrays 302-1 to 302 formed by the bumps 321.
This can be achieved by pouring a resin or the like having an insulating property and good heat dissipation property into the space between -n.

[0047]

As described above, according to the invention described in claim 1, a plurality of edge emitting type light emitting diodes are arranged on the same substrate in a direction parallel to the light emitting surface in one or more rows, and In a semiconductor light emitting device having an edge emitting light emitting diode array in which the spaces are electrically and spatially separated by a separation groove, in order to control the directivity of light emitted from the end face of the light emitting diode on the individual electrode of the light emitting diode. Since the light-shielding member is provided, the stray light of the light from the end surface of the edge-emitting LED array can be minimized when it is used as a light source for an optical printer or the like.
It is possible to realize high-quality printing without lowering the print quality.

According to the second aspect of the present invention, a plurality of edge emitting type light emitting diodes are arranged on the same base substrate in a line parallel to the light emitting surface, and the light emitting diodes are separated from each other by a separating groove. In a semiconductor light emitting device having an edge emitting type light emitting diode array that is electrically and spatially separated by, the individual electrode side of the light emitting diode is mounted by junction down on the base substrate that serves as a heat sink, and the base substrate is used. Since the directivity of the light emitted from the end face of the light emitting diode is controlled, the stray light of the light from the end face of the edge emitting type light emitting diode array can be minimized when used as a light source for an optical printer or the like. , High quality printing and the like can be realized without lowering the MTF.

According to a third aspect of the present invention, in the semiconductor light emitting device according to the first or second aspect, the edge emitting type light emitting diodes each include a double heterojunction. Therefore, the invention according to the first or second aspect. The same effect as can be obtained.

According to a fourth aspect of the present invention, in the semiconductor light emitting device according to the first or second aspect, each of the edge emitting type light emitting diodes includes a single heterojunction, a homojunction, or a diffusion P-N junction. So
The same effect as the invention according to claim 1 or 2 can be obtained.

According to a fifth aspect of the present invention, in the semiconductor light emitting device according to the first or second aspect, the edge emission is provided in a region which can serve as a slit for the light emitted from the base substrate and the edge emitting light emitting diode. Since the antireflection film is provided to suppress the reflection of the wavelength of the light emitted from the light emitting diode, the light emitted from the light emitting end face of the light emitting diode may be reflected by light or scattered light from a region that can be a slit. Stray light can be reduced by the antireflection film, and variations and instability of the light emission pattern (far field image) can be removed.

According to a sixth aspect of the present invention, in the semiconductor light emitting device according to the second aspect, since the individual electrode side of the light emitting diode is mounted on the base substrate by surface mounting with bumps, the height of the light emitting diode array is increased. The miniaturization of the density becomes easy in mounting.

According to a seventh aspect of the present invention, in the semiconductor light emitting device according to the second aspect, the individual electrode side of the light emitting diode is provided on the base substrate with an anisotropic conductive adhesive or an anisotropic conductive film. Since it is mounted by mounting, it is easy to mount the light emitting diode array in high density.

[Brief description of drawings]

FIG. 1 is a front view showing the first embodiment of the present invention and its A-
It is an A line sectional view.

FIG. 2 is a drawing for explaining the manufacturing process of the first embodiment.

FIG. 3 is a front view showing the second embodiment of the present invention and its A-
It is an A line sectional view.

FIG. 4 is a diagram schematically showing a connection relationship between the second embodiment and the third embodiment of the present invention.

FIG. 5 is a plan view showing a conventional semiconductor light emitting device.

FIG. 6 is a perspective view showing another conventional semiconductor light emitting device.

FIG. 7 is a perspective view showing another conventional semiconductor light emitting device.

FIG. 8 is a side view showing a part of the optical printer.

[Explanation of symbols]

 301 base substrate 302-1 to 302-n light emitting diode array 304 light shielding plate 305 individual electrode 306 common electrode 312 antireflection film 321 bump 325 anisotropic conductive adhesive 331, 332 metal 335 insulating film 360 wire bonding

Claims (7)

[Claims] 1. An end face in which a plurality of end face light emitting type light emitting diodes are arranged on the same substrate in one or more rows in a direction parallel to a light emitting face, and the respective light emitting diodes are electrically and spatially separated by a separating groove. A semiconductor light emitting device having a light emitting type light emitting diode array, characterized in that a light shielding member for controlling directivity of light emitted from the end face of the light emitting diode is provided on an individual electrode of the light emitting diode. . 2. A plurality of edge emitting light emitting diodes are arranged on the same base substrate in one or more rows in a direction parallel to a light emitting surface, and each light emitting diode is electrically and spatially separated by a separating groove. In the semiconductor light emitting device having the edge emitting type light emitting diode array, the individual electrode side of the light emitting diode is mounted on the base substrate serving as a heat sink by a junction down, and the light emitted from the end face of the light emitting diode on the base substrate. A semiconductor light-emitting device characterized in that the directivity of the device is controlled. 3. The semiconductor light emitting device according to claim 1, wherein each of the edge emitting type light emitting diodes includes a double heterojunction. 4. The semiconductor light emitting device according to claim 1 or 2, wherein said edge emitting type light emitting diode is a single heterojunction or homojunction or a P-N by diffusion.
A semiconductor light-emitting device comprising a junction. 5. The semiconductor light emitting device according to claim 1, wherein a wavelength of light emitted from the edge emitting light emitting diode is provided in a region which can be a slit for light emitted from the base substrate and the edge emitting light emitting diode. A semiconductor light emitting device, characterized in that an antireflection film is provided so as to suppress reflection. 6. The semiconductor light emitting device according to claim 2,
A semiconductor light emitting device in which the individual electrode side of the light emitting diode is mounted on the base substrate by surface mounting with bumps. 7. The semiconductor light emitting device according to claim 2, wherein
A semiconductor light emitting device, wherein the individual electrode side of the light emitting diode is mounted on the base substrate by surface mounting with an anisotropic conductive adhesive or an anisotropic conductive film.