JPH06291365A - Semiconductor light emitting device and its manufacturing method, optical detecting device, optical information processing device, and optical fiber module - Google Patents

Abstract

PURPOSE:To decrease ohmic resistance of elements caused by a multilayer reflecting film layer 2 in a semiconductor light emitting element with a current constricting structure and a semiconductor multilayer reflecting film layer. CONSTITUTION:On a p-GaAs substrate 1, a p-type multilayer reflecting film layer 2, a p-AlGaAs active layer 4 and an n-AlGaAs upper clad layer 5 are epitaxially grown. Then Be ions are implanted into the multilayer reflecting film layer 2 with a mask of an AZ resist film on a cap layer 6 thereby to decrease the ohmic resistance of the multilayer reflecting layer 2 in an ion- implanted region 8 to decrease the ohmic resistance of the element. Be ion is implanted into the upper clad layer 5 with the mask of the same AZ resist film and a current blocking region (a pn junction) in an ion-implanted region 9 is formed, and a region surrounded by the ion-implanted region 9 is formed as a region of a current path and a current constricting structure is formed.

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, a method for manufacturing the same, an optical detection device, an optical information processing device, a projector, and an optical fiber module. More specifically, the present invention relates to a semiconductor light emitting device such as a light emitting diode (LED) or a semiconductor laser device (LD) having a semiconductor multilayer reflective film layer and a method for manufacturing the same, and further to optical detection using the semiconductor light emitting device. The present invention relates to a device, an optical information processing device, a projector, and an optical fiber module.

[0002]

2. Description of the Related Art As a conventional example of a semiconductor light emitting device having a semiconductor multilayer reflective film, there is a semiconductor light emitting device P having a structure as shown in FIG. In this semiconductor light emitting device P,
On the p-GaAs substrate 301, p-type Al _0.2 Ga _0.8 A
The semiconductor multilayer reflective film layer 302 is formed by stacking 30 pairs of the s layer and the AlAs layer to form the semiconductor multilayer reflective film layer 302.
A p-Al _0.45 Ga _0.55 As lower clad layer 303,
p-Al _0.03 Ga _0.97 As active layer 304, n-Al _0.45
Ga _0.55 As upper clad layer 305, n-Al _0.1 Ga _0.9
As diffusion buffer layer 306, p-Al _0.45 Ga _0.55 As
A current blocking layer 307 and an n-Al _0.1 Ga _0.9 As cap layer 308 are laminated. Further, a light emitting window 310 is opened in the n-side electrode 309 provided on the upper surface of the cap layer 308, and the p-side electrode 3 is formed on the entire lower surface of the p-GaAs substrate 301.
11 is provided, and the Si diffusion region 312 is formed in the cap layer 308 and the current blocking layer 307 corresponding to the light emission window 310.
By partially forming a current blocking layer 307
Inverted to mold.

In such a semiconductor light emitting device P,
Since the current confinement structure is such that the current can pass through the current blocking layer 307 only through the Si diffusion region 312 inverted to the n-side, the light emitting region can be miniaturized, and when combined with the lens. Excellent collimating and light collecting properties. In addition to the current confinement structure, the active layer 304
Since the light emitted from the side to the side opposite to the light emission window 310 is reflected by the semiconductor multilayer reflection film layer 302 and guided to the light emission window 310, there is an advantage that the light emission efficiency is high.

[0004]

However, in a semiconductor light emitting device having a current confinement structure having such a semiconductor multilayer reflective film layer, the height of the device resistance due to the semiconductor multilayer reflective film layer (particularly, The p-type semiconductor multilayer reflective film layer is n
Type semiconductor multi-layer reflective film layer has very high resistance. ), There was a problem that the thermal saturation of the light output became severe and the light output was small. Further, since the element resistance is high, there is a problem that the driving voltage becomes high and it is difficult to drive the battery.

The present invention has been made in view of the drawbacks of the above conventional examples, and an object of the present invention is to dispose a semiconductor multilayer reflective film layer in a disordered manner except for a portion substantially above or below a current passage region. By reducing the resistance, or by disordering only the portion just above or below the current passage region, the element resistance due to the semiconductor multilayer reflective film layer is reduced.

[0006]

According to another aspect of the present invention, there is provided a semiconductor light emitting device having an active layer and a semiconductor multilayer reflective film layer, wherein a part of the semiconductor multilayer reflective film layer is disordered and the active layer is formed. The present invention is characterized in that current passage limiting means for limiting the current passage region serving as a passage for the injected current is provided.

In the above semiconductor light emitting device, the conductivity type of the semiconductor multilayer reflective film layer may be p type, and electrodes may be formed on the entire surface of the device except for most of the current passage region. Good.

In the above semiconductor light emitting device, the semiconductor multilayer reflective film layer may be disordered except for most of the portion just above or below the current passage region. In that case, the area of the disordered region of the semiconductor multilayer reflective film layer and the area of the current passage region can be made substantially equal.

In the semiconductor light emitting device, most of the portion just above or below the current passage region,
The semiconductor multilayer reflective film layer may be disordered.
In that case, the area of the disordered region of the semiconductor multilayer reflective film layer and the area of the current passage region can be made substantially equal.

In the semiconductor light emitting device, the semiconductor multilayer reflective film layer may be a current path limiting layer.

A first method of manufacturing a semiconductor light emitting device according to the present invention comprises the steps of forming a wafer having a double hetero structure having a semiconductor multilayer reflective film layer, introducing impurities into a predetermined position of the wafer using a mask, A step of forming or limiting a current passage region, and a step of disordering a part of the semiconductor multilayer reflective film layer by introducing impurities to a depth reaching at least the semiconductor multilayer reflective film layer using the same mask. It is characterized by that.

The impurity introduction method in this manufacturing method is as follows:
A diffusion method or an ion implantation method may be used, and zinc or beryllium may be used as an impurity.

A second method of manufacturing a semiconductor light emitting device according to the present invention comprises a step of forming a wafer having a semiconductor multilayer reflective film layer and at least one pn junction semiconductor layer above an active layer, and a solid phase on the wafer. Forming a diffusion source,
The method is characterized by including the step of diffusing the pn junction semiconductor layer formed above the active layer and the semiconductor multilayer reflective film layer using the diffusion source.

A third method of manufacturing a semiconductor light emitting device according to the present invention comprises a step of forming a wafer having at least one pn junction semiconductor layer above a semiconductor multilayer reflective film layer and an active layer, and a solid phase on the wafer. Forming a diffusion source,
A step of performing diffusion using this diffusion source until it penetrates a pn junction semiconductor layer formed above the active layer, and performing ion implantation at least to a depth reaching the semiconductor multilayer reflective film layer using this solid-phase diffusion source as a mask. Is characterized by.

The semiconductor light emitting device according to the present invention can be used in an optical detection device, an optical information processing device, a light projector, and an optical fiber module.

[0016]

In the semiconductor light emitting device of the present invention, since the current passage limiting means for limiting the current passage region is provided, the injected current can be concentrated in the minute region of the active layer, which is high. A small amount of light emission (conversely, it is possible to increase the light emission diameter) can be obtained with the light emission efficiency. In addition, since the light emitted to the side opposite to the light emitting side can be reflected by the semiconductor multilayer reflective film layer, high luminous efficiency can be obtained.

Moreover, since a part of the semiconductor multilayer reflection film layer is disordered, the resistance of the semiconductor multilayer reflection film layer becomes small in the disordered region, and the current becomes a semiconductor multilayer in the disordered region of small resistance. It can pass through the reflective film layer, and the device resistance of the semiconductor light emitting device becomes small. For this reason, the operating voltage of the semiconductor light emitting element is reduced. Moreover, since the element resistance is reduced, the thermal saturation of the light output is also reduced, and the light output can be increased.

The first semiconductor light emitting device according to the present invention
In the manufacturing method of (1), since the current passage region (current passage limiting region) is formed using the same mask and the semiconductor multilayer reflection film layer is partially disordered, the current passage region (current passage limiting region) is formed. (Region) and the disordered region of the semiconductor multilayer reflective film layer can be easily aligned without any alignment, and the manufacturing process can be simplified.

The second aspect of the semiconductor light emitting device according to the present invention
In the manufacturing method described above, since the diffusion is performed until it penetrates the pn junction semiconductor layer and the semiconductor multilayer reflective film layer using the solid phase diffusion source formed on the wafer, the current passage region (current passage restriction region) Formation and disordering of the multilayer reflective film layer can be performed at the same time, and the alignment of the current path region (current path restriction region) and the disordered region of the semiconductor multilayer reflective film layer can be easily performed without alignment, and manufacturing The process can be simplified.

The third aspect of the semiconductor light emitting device according to the present invention is as follows.
In the manufacturing method of (1), since the solid-phase diffusion source for diffusing the pn junction semiconductor layer is used as a mask for ion implantation into the semiconductor multilayer reflective film layer, it is not necessary to separately form a mask for ion implantation, The alignment of the current passage region (current passage restriction region) and the disordered region of the semiconductor multilayer reflective film layer can be easily performed without alignment, and the manufacturing process can be simplified.

Further, since the semiconductor light emitting device of the present invention has a small light emission diameter and can increase the light output, it can be used in an optical detection device, an optical information processing device, a light projector, and an optical fiber module. Various optical devices with good performance can be manufactured.

[0022]

1 (a) and 1 (b) are plan and sectional views showing a surface emitting type AlGaAs semiconductor light emitting device A1 according to a first embodiment of the present invention, and FIGS. 2 (a), 2 (b) and 2 (c). ) (D) is sectional drawing which shows the manufacturing procedure of this semiconductor light-emitting device A1. This semiconductor light emitting device Al will be described according to the manufacturing procedure. First, 30 pairs of Al _0.2 are formed on the p-GaAs substrate 1 by using the MBE method or the MOCVD method.
P-type multilayer reflective film layer 2 composed of Ga _0.8 As layer and AlAs layer, p-Al _0.35 Ga _0.65 As lower cladding layer 3, p
-Al _0.03 Ga _0.97 As active layer 4, n-Al _0.35 Ga
_{A 0.65} As upper cladding layer 5 and an n-Al _0.1 Ga _0.9 As cap layer 6 are sequentially epitaxially grown. This wafer has a double heterostructure.

Although the multilayer reflective film layer 2 is an Al _0.2 Ga _0.8 As / AlAs layer consisting of 30 pairs here,
The composition and the number of pairs of the multilayer reflective film layer 2 are not particularly limited (the same applies to each of the examples after this example).

After that, as shown in FIG. 2A, A is formed in a desired shape and size at a desired position on the cap layer 6 (for example, a circle having a diameter of 50 μm at the center of the cap layer 6).
A Z resist coating 7 is formed to partially cover the cap layer 6.

Then, as shown in FIG. 2 (b), Be ions are implanted using the AZ resist coating 7 as a mask to form an ion implantation region 8 (represented by a satin pattern in FIGS. 1 and 2). At this time, the lower cladding layer 3 and the GaA
s B is formed on the multilayer reflective film layer 2 so that the upper and lower ends of the ion implantation region (Be ion distribution region) 8 are located in the substrate 1.
implant e-ions. Next, as shown in FIG. 2C, the same AZ resist film 7 is used as a mask and the upper cladding layer 5 is formed.
Be ions are implanted again to form the ion-implanted region 9 (represented by a satin pattern in FIGS. 1 and 2) so that the upper end and the lower end of the ion-implanted region 9 are in the upper cladding layer 5.

However, in this ion implantation step, regardless of the order of ion implantation, after the ion implantation region 9 of the upper cladding layer 5 is formed, the ion implantation region 8 of the portion of the multilayer reflective film layer 2 is formed. You may. Further, the Be ion implantation depth in the ion implantation region 8 is not limited to the depth shown in the figure, and the entire thickness of the multilayer reflective film layer 2 may be the ion implantation region 8. Further, regarding the Be ion implantation depth in the ion implantation region 9, it is sufficient that the lower surface of the ion implantation region 9 is in the n-type region above the active layer 4.

In this way, when Be ions are implanted in the upper cladding layer 5 except for a partial region to form the ion-implanted region 9, the conductivity type of the n-type upper cladding layer 5 is inverted to the p-type in the ion-implanted region 9. Therefore, a pn junction surface is formed at the interface between the lower surface of the p-type ion implantation area 9 and the n-type upper cladding layer 5 (area hatched in FIG. 1). This p
The n-junction surface is reverse biased when a drive voltage is applied to the semiconductor light emitting element Al, and a current i is applied to the ion implantation region 9.
Can't flow. On the other hand, in the region where the ion implantation region 9 is not formed, the flow of the current i is not hindered. Therefore, the ion implantation region 9 in the upper cladding layer 5 is
The region formed with is the current blocking region, and the region surrounded by the ion-implanted region 9 is the current passage region 10. Only the limited current passage region 10 between the active layer 4 and the cap layer 6 is formed. It has a current constriction structure in which the current i flows.

Further, since Be ions are implanted into the entire thickness of the multilayer reflective film layer 2 except for the portion directly below the current passage region 10 to form the ion-implanted region 8, the multi-layer reflection in this ion-implanted region 8 is performed. The membrane layer 2 is disordered. That is, the crystal structure of the disordered multilayer reflective film layer 2 is almost completely amorphized. As a result, the reflection effect of the multilayer reflective film layer 2 disappears in this portion, but the resistance of the multilayer reflective film layer 2 is reduced, and the resistance of the entire element is reduced.

According to the method described above, the same mask (AZ resist coating 7) is used for Be implantation for forming the current passage region 10 and Be implantation for disordering the multilayer reflective film layer 2. Moreover, since the ion species to be implanted are the same, the multilayer reflective film layer 2 can be easily disordered in a region other than immediately below the current passage region 10 without requiring alignment work such as a mask. That is, the current confinement structure and the disordering of the multilayer reflective film layer 2 can be achieved by a simple process.

After that, the AZ resist film 7 used as a mask is removed from the top of the cap layer 6. Furthermore, except for the regions above the ion implantation regions 8 and 9, the cap layer 6 is formed.
An AZ resist film 11 having substantially the same shape and size as the AZ resist film 7 is formed again on the top surface of the AZ resist film 11 as shown in FIG. 2 (d). An electrode material is vapor-deposited thereon to form the n-side electrode 12. Then, the AZ resist film 11 is peeled off to open a circular light extraction window 13 in the n-side electrode 12 by a lift-off method. Finally, G
The p-side electrode 14 is provided on the entire lower surface of the aAs substrate 1 to obtain the semiconductor light emitting device Al as shown in FIG.

Here, AZ of the mask for ion implantation is used.
The resist film 7 and the lift-off mask AZ resist film 11 were separated, and after removing the AZ resist film 7, a new AZ resist film 11 was formed.
The resist coatings 7 and 11 may be used together. That is,
AZ resist coating 7 used as a mask during ion implantation
May be left without being removed and used as it is as a mask for lift-off. By doing so, the step of removing the AZ resist film 7 and the step of forming the AZ resist film 11 can be omitted, and the manufacturing process of the semiconductor light emitting device A1 can be simplified.

However, when a driving voltage is applied between the n-side electrode 12 and the p-side electrode 14, the current i flowing from the p-side electrode 14 is activated through the inner peripheral portion of the ion implantation region 8 having a small resistance. It is injected into the region of the layer 4 facing the current passage region 10 and further flows to the n-side electrode 12 through the current passage region 10 surrounded by the ion implantation region 9. Therefore, in the active layer 4, light is emitted in a minute region facing the current passage region 10, and light emitted upward from the active layer 4 passes through the current passage region 10 and is emitted to the outside from the light extraction window 13. Further, the light emitted downward from the active layer 4 is reflected upward in the non-disordered region of the multilayer reflective film layer 2 and emitted to the outside through the upper light extraction window 13.

In such a semiconductor light emitting device Al, since the current confinement structure is adopted, it is possible to obtain a device having a small light emission diameter and high external light emission efficiency. Moreover, since a part of the multilayer reflection film layer 2 having a large resistance is disordered, the current can pass through the multilayer reflection film layer 2 through a disordered region having a small resistance, and the p-side electrode 14 and the n-side electrode 14
The element resistance with the side electrode 12 is reduced, and the operating voltage can be reduced. Therefore, according to the present invention, by lowering the element resistance, it is possible to suppress the amount of heat generated thereby, so that it is possible to suppress the saturation of the optical output due to the heat generation, and the high output operation of the semiconductor light emitting element Al. It will be possible. Further, since the temperature rise of the element can be suppressed, the life can be extended. In particular, since the device resistance can be reduced while achieving a minute light emission diameter, the present invention is very effective when the light emitting region is miniaturized.

In the first embodiment described above, Be ions are implanted to form the ion-implanted regions 8 and 9, but the ion species is not limited to Be, as long as it is a p-type element. Further, the ions implanted in the ion implantation region 8 and the ions implanted in the ion implantation region 9 may be different elements. Further, the ions implanted in the ion implantation region 9 may be hydrogen ions. When hydrogen ions are used, the region into which hydrogen ions are implanted becomes a high resistance layer, so that the ion implantation region 9 serves as a current blocking layer and a current constriction structure is realized.

Although the AZ resist coatings 7 and 11 and the light extraction window 13 are circular in the above embodiment, the shape is not limited to a circular shape, and the shape of the light extraction window 13 and the cross-sectional shape of the current passage region 10 are not limited thereto. Need not be the same (also in the examples below).

FIGS. 3A and 3B are a plan view and a sectional view showing a semiconductor light emitting device A2 according to a second embodiment of the present invention. In this semiconductor light emitting device A2, the structure as in the first embodiment is realized in the light emitting device in which the multilayer reflective film layers 15 and 2 are provided above and below the active layer 4. Specifically, in addition to the structure of the semiconductor light emitting device A1 according to the first embodiment, 30 pairs of Al _0.2 Ga _0.8 As layers and an upper cladding layer 5 and a cap layer 6 are provided above the active layer 4. An n-type multilayer reflective film layer 15 made of an AlAs layer is provided. When the n-type multilayer reflective film layer 15 and the p-type multilayer reflective film layer 2 are provided above and below the active layer 4 like the semiconductor light emitting device A2, a vertical cavity surface emitting laser having a current constriction structure is manufactured. Therefore, the element resistance of the vertical cavity surface emitting laser can be reduced.

4A and 4B are bottom emission type AlGaAs semiconductor light emitting device A3 according to the third embodiment of the present invention.
And FIG. 5A, FIG. 5B, and FIG.
FIG. 3D is a sectional view showing the procedure for manufacturing the semiconductor light emitting device A3. The semiconductor light emitting device A3 will be described according to the manufacturing procedure. First, by using the MBE method, the MOCVD method or the like, the n-Al is formed on the n-GaAs substrate 21.
_0.35 Ga _0.65 As Upper cladding layer 22, p-Al _0.03 Ga
_0.97 As active layer 23, p-Al _0.35 Ga _0.65 As lower cladding layer 24, 30 pairs of Al _0.2 Ga _0.8 As layer and Al
P-type multilayer reflective film layer 25 composed of As layer, p-GaAs
The cap layer 26 is sequentially epitaxially grown. This wafer has a double heterostructure.

Thereafter, as shown in FIG. 5A, a desired shape and size are obtained at desired positions on the cap layer 26 (for example, a circular shape having a diameter of 50 μm is formed in the central portion of the cap layer 26).
To form an AZ resist film 27, and partially cover the cap layer 26.

Then, as shown in FIG. 5B, Be ions are implanted using the AZ resist film 27 as a mask to form an ion implantation region 28 (represented by a satin pattern in FIGS. 4 and 5). At this time, the multilayer reflective film layer 25 is arranged so that the upper and lower ends of the ion implantation region (Be ion distribution region) 28 are located in the cap layer 26 and the lower cladding layer 24.
Be ions are implanted into. Next, as shown in FIG. 5C, using the same AZ resist coating 27 as a mask, Si ions are implanted into the cap layer 26 to implant the ion-implanted region 2.
9 (represented by a satin pattern in FIGS. 4 and 5),
The upper and lower ends of the ion implantation region 29 are cap layers 26.
Try to come inside.

However, in this step of implanting ions, the cap layer 26 is irrelevant regardless of the order of implanting ions.
After forming the ion-implanted region 29 on the substrate, the multilayer reflective film layer 2
The ion-implanted region 28 may be formed at the portion 5. Further, the implantation depth of Be ions in the ion implantation region 28 is not limited to the depth shown in the figure,
The entire thickness of the multilayer reflective film layer 25 may be the ion implantation region 28. Further, regarding the implantation depth of Si ions in the ion implantation region 29, the lower surface of the ion implantation region 29 may be in the p-type region above the active layer 23.

In this way, when Be ions are implanted in the cap layer 26 except for a partial region to form the ion-implanted region 29, the p-type cap layer 2 is formed in the ion-implanted region 29.
Since the conductivity type of No. 6 is inverted to the n type, the interface between the n type ion implantation region 29 and the p type cap layer 26 (see FIG. 4).
The pn junction surface is formed in the hatched area of FIG. This pn junction surface becomes a reverse bias when a drive voltage is applied to the semiconductor light emitting device A3, and the current i cannot flow in the ion implantation region 29. On the other hand, in the region where the ion implantation region 29 is not formed, the flow of the current i is not disturbed. Therefore, in the cap layer 26, the region in which the ion-implanted region 29 is formed becomes the current blocking region, and the region surrounded by the ion-implanted region 29 becomes the current passage region 30, and the active layer 23 and the cap layer 26 are separated from each other. Between them, a current constriction structure is provided in which the current i flows only in the limited current passage region 30.

Further, since the ion implantation region 28 is formed by implanting Be ions into the entire thickness of the multilayer reflective film layer 25 except the portion corresponding to the current passage region 30, the ion implantation region 28 is provided with the multilayer reflection. The film layer 25 is disordered, and the resistance of the multilayer reflective film layer 25 is reduced in this portion, and the resistance of the entire element is reduced.

According to the method as described above, the same mask (AZ resist coating 7) is used for Si implantation for forming the current passage region 30 and Be implantation for disordering the multilayer reflective film layer 25. Therefore, the current passage region 3 can be easily formed without requiring mask alignment work.
In the area other than the portion corresponding to 0, the multilayer reflective film layer 25
Can be chaotic. That is, the current confinement structure and the disordering of the multilayer reflective film layer 25 can be achieved by a simple process.

After that, the AZ resist film 27 used as a mask is removed from above the cap layer 26, and the p-side electrode 34 is provided on the entire surface of the cap layer 26.

Then, as shown in FIG. 5 (d), the wafer is turned upside down so that the GaAs substrate 21 side is facing up, and any region on the GaAs substrate 21 except the regions above the ion implantation regions 28 and 29. An AZ resist film 31 having a shape and a size (for example, a circle having a diameter of 100 μm in the central portion) is formed, and an electrode material is vapor-deposited from the AZ resist film 31 onto the GaAs substrate 21 using the AZ resist film 31 as a mask. The n-side electrode 32 is formed. Then, the AZ resist film 31 is peeled off to form a circular light extraction window 33 in the n-side electrode 32 by a lift-off method. Finally, using the n-side electrode 32 as a mask, for example, NH ₄ : H ₂ O ₂
= 1: 10 or the like, and the upper cladding layer 22 is formed by using an etching solution.
The GaAs substrate 21 is etched until the temperature reaches, and a light extraction port 35 communicating with the light extraction window 33 is opened in the GaAs substrate 21 to obtain a semiconductor light emitting device A3 as shown in FIG.

However, if the material of the GaAs substrate 21 is transparent to the emission wavelength, the step of opening the light extraction port 35 in the GaAs substrate 21 can be omitted (for the back emission type semiconductor light emitting device, The same applies to the examples subsequent to this example).

Even in this semiconductor light emitting device A3, when a current is injected from the p-side electrode 34 into the active layer 23 through the current passage region 30 surrounded by the ion implantation region 29, the minute amount of the active layer 23 is reduced. Light emitted in the region and emitted upward from the active layer 23 is emitted to the outside through the light extraction port 35. Further, the light emitted downward from the active layer 23 is reflected upward in the non-disordered region of the multilayer reflective film layer 25,
The light is emitted from the light extraction port 35 to the outside. Therefore, the semiconductor light emitting device A3 of the back emission type in which light is emitted from the substrate side can be obtained, and the device resistance can be reduced while achieving a small light emission diameter.

In the third embodiment, Be ions are implanted to form the ion-implanted region 28, but the ion species is not limited to Be as long as it is a p-type element. Further, in order to form the ion implantation region 29, Si is used.
Although ions are implanted, the ion species is not limited to Si and may be any type as long as it is an n-type element. In addition, the ion implantation area 29
The ions implanted into may be hydrogen ions. When hydrogen ions are used, the region into which the hydrogen ions are implanted becomes a high resistance layer, so that the ion implantation region 29 serves as a current blocking layer, and a current constriction structure is similarly realized.

Although not shown, in the semiconductor light emitting device A3 having the structure of the third embodiment, the active layer 23 and Ga are
30 pairs of Al _0.2 Ga _0.8 As between the As substrate 21 and
Vertical cavity surface emitting laser having a current constriction structure with the n-type multilayer reflective film layer and the p-type multilayer reflective film layer 25 above and below the active layer 23 by providing an n-type multilayer reflective film layer including a layer and an AlAs layer. Can be manufactured.

FIGS. 6A and 6B are a plan view and a sectional view showing a semiconductor light emitting device A4 according to a fourth embodiment of the present invention. This semiconductor light emitting device A4 is a back emission semiconductor light emitting device similar to the semiconductor light emitting device A3 of the third embodiment, but Si ions are implanted in the p-type lower cladding layer 24, and the current confinement is caused. The ion-implanted region 29 for realizing the structure is arranged on the back surface side (upper side) than the ion-implanted region 28 for disordering the multilayer reflective film layer 25. The semiconductor light emitting device A4 having such a structure can also achieve the same effects as the semiconductor light emitting device A3 of the third embodiment. In this embodiment, the ion-implanted region 29 is not necessarily the lower cladding layer 24.
However, the p-type region may be located on the surface side (lower side) of the active layer 23. Further, the ions to be implanted are not limited to Si and may be any n-type element.

7A and 7B are a plan view and a sectional view showing a semiconductor light emitting device A5 according to a fifth embodiment of the present invention. In this embodiment, the multilayer reflective film layer 2 is formed by diffusion.
It is a disordered version of 5. This semiconductor light emitting device A5
In this case, a mask 27 is provided on the surface of the cap layer 26, Si ions are implanted into the p-type lower cladding layer 24 to form an ion implantation region 29, and a current confinement structure is realized in the lower cladding layer 24. is doing. Further, by diffusing Zn from above the cap layer 26 covered with the mask 27, Zn is diffused from the surface of the cap layer 26 to the lower clad layer 24 except for the region corresponding to the current passage region 30. A diffusion region 36 (shown by cross hatching in FIG. 7) is formed, and the multilayer reflection film layer 25 is disordered by impurity diffusion in the impurity diffusion region 36 and has a low resistance. Of course, in this case as well, the diffusion element is not limited to Zn and may be a p-type element.

FIGS. 8A and 8B are bottom emission type AlGaAs semiconductor light emitting device A6 according to the sixth embodiment of the present invention.
9A, 9B, and 9C are plan views and cross-sectional views illustrating
FIG. 6D is a sectional view showing the procedure for manufacturing the semiconductor light emitting device A6. This semiconductor light emitting device A6 will be described according to the manufacturing procedure. First, by using the MBE method or the MOCVD method, the n-Al is formed on the n-GaAs substrate 41.
_0.35 Ga _0.65 As Upper clad layer 42, p-Al _0.03 Ga
_0.97 As active layer 43, p-Al _0.35 Ga _0.65 As lower cladding layer 44, 30 pairs of Al _0.2 Ga _0.8 As layer and Al
P-type multilayer reflective film layer 45 made of As layer, p-GaAs
A diffusion buffer layer 46, an n-Al _0.35 Ga _0.65 As current blocking layer 47, and a p-GaAs cap layer 48 are sequentially epitaxially grown. This is a pnpn junction structure.

Thereafter, as shown in FIG. 9A, a desired shape and size are provided at desired positions on the cap layer 48 (for example, a circular shape having a diameter of 50 μm is formed in the central portion of the cap layer 48).
Then, a p-type diffusion source (eg, SiO ₂ —ZnO film) 4 is formed by applying a diffusing agent (OCD) having a coating property.
9 is formed. Alternatively, the p-type diffusion source 49 may be formed on the cap layer 48 by using a sputtering method or the like. Then, by performing heat treatment using, for example, an infrared lamp flash annealing furnace, p-Zn is diffused from the mask of the p-type diffusion source 49. Zn is diffused at least until it penetrates the current blocking layer 47. In the example of FIG. 9B, Zn is diffused until it reaches the diffusion buffer layer 46, and Z
An n-diffusion region 50 (a region hatched in FIGS. 8 and 9) is formed. The diffusion buffer layer 46
In, the diffusion rate of Zn is slower than that of the current blocking layer 47.

The pn junction surface between the current blocking layer 47 and the diffusion buffer layer 46 (the hatched area in FIG. 8) is reverse biased when a drive voltage is applied to the element, and the current i does not flow. On the other hand, a Zn diffusion region 50 in which p-Zn is diffused
Since the conductivity type of the n-type current blocking layer 47 is inverted to the p-type, the flow of the current i is not disturbed. Therefore, Zn
The outside of the diffusion region 50 is a current blocking region, only the Zn diffusion region 50 is a current passage region 51, and the current confinement structure is limited to the minute Zn diffusion region 50.

Then, as shown in FIG. 9C, the above p
Be ions are implanted using the mold diffusion source 49 as a mask to form an ion implantation region 52 (represented by a satin pattern in FIGS. 8 and 9). At this time, Be ions are implanted in the multilayer reflective film layer 45 so that the upper and lower ends of the ion implantation regions (Be ion distribution regions) 52 are located in the diffusion buffer layer 46 and the lower cladding layer 44, respectively.

However, Be in the ion implantation region 52
The ion implantation depth is not limited to the depth shown in the figure, and the entire thickness of the multilayer reflective film layer 45 may be the ion implantation region 52. Further, the ions to be implanted are not limited to Be ions, but may be any p-type element.

In this way, the ion implantation region 52 is formed by implanting Be ions in the entire thickness of the multilayer reflection film layer 45 except the portion corresponding to the current passage region 51. Therefore, in the ion implantation region 52, the multilayer reflection film is formed. The layer 45 is disordered, and the resistance of the multilayer reflective film layer 45 is reduced in this portion.

Further, according to the above method, since the p-type diffusion source 49 for diffusing Zn is used as a mask for ion implantation, the current passage region can be easily formed without the need for mask alignment work. The multilayer reflective film layer 45 can be disordered in a region other than the portion corresponding to 51. That is, the current confinement structure and the disordering of the multilayer reflective film layer 45 can be achieved by a simple process.

After that, the p-type diffusion source 4 used as a mask
9 is removed from the top of the cap layer 48, and the p-side electrode 53 is provided on the entire surface of the cap layer 48.

Then, as shown in FIG. 9D, the wafer is turned upside down so that the GaAs substrate 41 side faces up, and the surface of the GaAs substrate 41 is extended to the desired shape and size ( For example, a diameter of 100μ in the center
An AZ resist film 54 is formed in a circle of m), and an electrode material is vapor-deposited from above by using the AZ resist film 54 as a mask to form an n-side electrode 55 on the GaAs substrate 41. Then, the AZ resist film 54 is peeled off to open a circular light extraction window 56 in the n-side electrode 55 by the lift-off method. Finally, using the n-side electrode 55 as a mask, the GaAs substrate 41 is etched until it reaches the upper clad layer 42 using an etching solution such as NH ₄ : H ₂ O ₂ = 1: 10, and communicates with the light extraction window 56. Light outlet 57
To a GaAs substrate 41 to obtain a semiconductor light emitting device A6 as shown in FIG.

In this semiconductor light emitting device A6, when the current i is injected from the p-side electrode 53 to the active layer 43 through the Zn diffusion region 50 which becomes the current passage region 51, the active layer 4 is formed.
Light emitted in the minute region of 3 and emitted upward from the active layer 43 is emitted to the outside through the light extraction port 57. Further, the light emitted downward from the active layer 43 is reflected by the multilayer reflective film layer 45.
The light is reflected upward in a region not disordered and is emitted to the outside from the light extraction port 57. Therefore, the semiconductor light emitting device A6 of the back emission type in which light is emitted from the substrate side is obtained, and the device resistance can be reduced while achieving a small light emission diameter.

Although the current passage region 51 is formed by diffusing the p-type impurity in the sixth embodiment, the current passage region 51 may be formed in a similar region by ion implantation of Be ions or the like.

FIGS. 10A and 10B are a plan view and a sectional view showing a semiconductor light emitting device A7 according to a seventh embodiment of the present invention. This semiconductor light emitting device A7 is based on the semiconductor light emitting device A1 of the first embodiment and has a Ga
It is a top emission type that emits light to the side opposite to the As substrate 1. That is, like the semiconductor light emitting device A1, GaA
Al _0.2 Ga _0.8 As / AlAs layer (30
A pair) p-type multilayer reflective film layer 2, p-Al _0.35 Ga
_0.65 As lower cladding layer _{3, p-Al 0.03 Ga 0.} 97 As active layer _{4, n-Al 0.35 Ga 0.65} As upper cladding layer 5, n
-Al _0.1 Ga _{0 .9} While As cap layer 6 is obtained by growing, p-A between the upper cladding layer 5 and the cap layer 6
l _0.35 Ga _0.65 As current blocking layer 60 is formed, and an n-type impurity (for example, Si) is diffused from the cap layer 6 to the upper cladding layer 5 so as to penetrate the current blocking layer 60 to form an impurity diffusion region 61. A current constriction structure is realized by using the impurity diffusion region 61 as a current passage region 62. Further, in a region except directly under the current passage region 62, an ion implantation region 8 is formed by implanting Be ions into the multilayer reflective film layer 2 between the GaAs substrate 1 and the lower cladding layer 3. In the ion-implanted region 8, the multilayer reflective film layer 2 is disordered. The method for manufacturing the semiconductor light emitting device A7 can be easily implemented with reference to the method for manufacturing the semiconductor light emitting device A6 in FIG.

FIGS. 11A and 11B are a plan view and a sectional view showing a semiconductor light emitting device A8 according to an eighth embodiment of the present invention. While the semiconductor light emitting device A7 of FIG. 10 forms the current passage region 62 by diffusion of Si or the like, the semiconductor light emitting device A8 is formed by implanting n-type ions such as Si so as to penetrate the current blocking layer 60. An ion-implanted region 66 is formed, and the ion-implanted region 66 is used as a current passage region 67 to realize a current constriction structure.

FIGS. 12A and 12B are bottom emission type AlGaAs semiconductor light emitting device A according to the ninth embodiment of the present invention.
9A and 9B are a plan view and a cross-sectional view showing 9;
FIG. 7A is a cross-sectional view showing the procedure for manufacturing the semiconductor light emitting device A9. The semiconductor light emitting device A9 will be described according to the manufacturing procedure. First, n-Al _0.35 Ga is formed on the n-GaAs substrate 71 by using the MBE method or the MOCVD method.
_0.65 As upper clad layer 72, p-Al _0.03 Ga _0.97 As
Active layer 73, p-Al _0.35 Ga _0.65 As lower cladding layer 7
P-type multilayer reflective film layer 75 consisting of 4, 30 pairs of Al _0.2 Ga _0.8 As layer and AlAs layer, n-Al _0.35 Ga _0.65
The As current blocking layer 76 and the p-GaAs cap layer 77 are sequentially epitaxially grown. This is a pnpn junction structure.

Thereafter, as shown in FIG. 13A, a desired shape and size (for example, a circle having a diameter of 50 μm at the center of the cap layer 77) is formed at a desired position on the cap layer 77, for example. By applying a diffusing agent (OCD) having a coating property, a p-type diffusion source (for example, SiO ₂ —ZnO) is formed.
A film) 78 is formed. Alternatively, the p-type diffusion source 78 may be formed on the cap layer 77 by using a sputtering method or the like. Then, as shown in FIG. 13B, heat treatment is performed using, for example, an infrared lamp flash annealing furnace to diffuse p-Zn from the mask of the p-type diffusion source 78. Zn diffuses through the current blocking layer 76 and the multilayer reflective film layer 75 until it reaches the lower cladding layer 74.
A diffusion region 79 is formed.

The pn junction surface (the hatched area in FIG. 12) between the current blocking layer 76 and the multilayer reflective film layer 75 is reverse biased when a drive voltage is applied to the element, and the current i does not flow. On the other hand, a Zn diffusion region 79 in which p-Zn is diffused
Becomes the current passage region 80 because the conductivity type of the n-type current blocking layer 76 is inverted to the p-type, and the flow of the current i is not hindered. Therefore, the outside of the Zn diffusion region 79 is a current blocking region, and only the Zn diffusion region 79 is the current passage region 80.
The current confinement structure is such that the current passage is limited to only this minute current passage region 80.

The multilayer reflective film layer 75 is formed by diffusing Zn.
By gently disordering, it is possible to disorder only the vicinity of the interface of the layers forming the multilayer reflective film layer 75, so that the multilayer reflective film layer 75 is mildly disordered in the Zn diffusion region 79. Thus, the multilayer reflective film layer 75
Is slightly disordered, the slightly disordered region 81 can maintain a high reflectance comparable to that of the non- disordered multilayer reflective film layer 75, and corresponds to the current passage region 80. The resistance of the multilayer reflective film layer 75 can be reduced in the region, and as a result, the resistance of the entire element can be reduced. Therefore, in this embodiment, the current passage region 80 can be formed and the multilayer reflection film layer 75 can be disordered by one diffusion process, and the current passage region 80 can be easily formed without the need for mask alignment work. The multilayer reflective film layer 75 can be disordered in the corresponding region, and the current confinement structure and the multilayer reflective film layer 7 can be formed by a simple process.
A disorder of 5 can be achieved.

After that, the p-type diffusion source 7 used as a mask
8 is removed from the top of the cap layer 77, and the p-side electrode 82 is provided on the entire surface of the cap layer 77.

Then, as shown in FIG. 13C, the wafer is turned upside down so that the GaAs substrate 71 side faces up, and the Zn
On the extension of the diffusion region 79, the surface of the GaAs substrate 71 has an arbitrary shape and size (for example, a diameter of 100 at the center).
An AZ resist film 83 is formed in a circular shape of μm), and an electrode material is vapor-deposited from above by using the AZ resist film 83 as a mask to form an n-side electrode 84 on the GaAs substrate 71.
Then, the AZ resist film 83 is peeled off to form a circular light extraction window 85 on the n-side electrode 84 by a lift-off method.
To open. Finally, using the n-side electrode 84 as a mask, the GaAs substrate 71 is etched until it reaches the upper cladding layer 72 by using an etching solution such as NH ₄ : H ₂ O ₂ = 1: 10, and it is connected to the light extraction window 85. Light extraction port 8
6 is opened in the GaAs substrate 71 to obtain a semiconductor light emitting device A9 as shown in FIG.

In this semiconductor light emitting device A9, the p-side electrode 8 is passed through the current passage region 80 and the Zn diffusion region 79 which becomes the lightly disordered region 81 of the multilayer reflective film layer 75.
When a current i is injected from 2 to the active layer 73, the active layer 73
The light emitted in the minute region of the above and emitted upward from the active layer 73 is emitted to the outside through the light extraction port 86. Also,
The light emitted downward from the active layer 73 is reflected upward in the lightly disordered region 81 of the multilayer reflective film layer 75, and is emitted to the outside from the light extraction port 86. As a result, the semiconductor light emitting device A9 of the back emission type in which light is emitted from the substrate side can be obtained, and the device resistance can be reduced while achieving a small light emission diameter.

In the ninth embodiment, the current passage region 80 is formed by diffusing the p-type impurity and the multilayer reflective film layer 75 is lightly disordered. A lightly disordered region 81 of the passage region 80 and the multilayer reflective film layer 75 may be formed.

By lightly disordering a part of the multilayer reflective film layer as in the semiconductor light emitting device A9 of FIG. 12, the resistance of the disordered region of the multilayer reflective film layer is reduced and the disordered region is formed. The method of maintaining the high reflectance of the multilayer reflective film layer in the region can be applied to a structure other than that shown in FIG. For example, the semiconductor light emitting device A10 shown in FIGS. 14A and 14B is the semiconductor light emitting device A1 of FIG.
It has a structure similar to that of FIG.
The semiconductor light emitting device A11 shown in FIG.
The semiconductor light emitting devices A10 and A11 each have a structure similar to that of No. 2 and the Be is formed in the multilayer reflective film layer 2 in most of the portion just below the current passage region 10 surrounded by the Be ion ion implantation region 9. Ions are implanted, and the multilayer reflection film layer 2 is lightly disordered in the ion implantation region 91, and the resistance is lowered while maintaining the high reflectance of the lightly disordered ion implantation region 91. 16 (a) and 16 (b)
The semiconductor light emitting device A12 shown in FIG. 17 has a structure similar to that of the semiconductor light emitting device A7 shown in FIG.
The semiconductor light emitting device A13 shown in (b) has a structure similar to that of the semiconductor light emitting device A8 of FIG. 11, and in each case, Si is diffused so as to penetrate the current blocking layer 60,
Alternatively, Be ions are implanted in the multilayer reflective film layer 2 in a large part directly below the current passage regions 62 and 67 formed by implanting Si ions to make them lightly disordered, and the high reflectance of the lightly disordered ion-implanted regions 91 is maintained. While lowering the resistance.

In each of the above-mentioned embodiments, the current path limiting means is specially provided. However, if a part of the multilayer reflective film layer is lightly disordered, the current flows into the high resistance non-disordered multilayer reflective film layer. Hardly flows, and flows into a disordered region having a low resistance. Therefore, the multilayer reflective film layer can have the function of the current path limiting means without providing the current path limiting means. For example, in the semiconductor light emitting device A14 (fourteenth embodiment) shown in FIGS. 18A and 18B, in the wafer having the same structure as the semiconductor light emitting device A1 of FIG. Is applied to lightly disorder a small area of the multilayer reflective film layer 2, and the ion implantation region 91 has a lower resistance than the other regions of the multilayer reflective film layer 2 while maintaining a high reflectance. Therefore, the current i is injected into the active layer 4 through the ion-implanted region 91 having a low resistance to reduce the element resistance, and at the same time, the ion-implanted region 91 becomes the current passage region 92 and the current constriction structure is formed. Has been realized. Therefore, according to such a structure, a target semiconductor light emitting device can be obtained with a very simple structure.

Further, in each of the above-described embodiments, the ion implantation region and the region in which ions are not implanted are reversed, or the impurity diffusion region and the region in which impurities are not diffused are reversed, so that the current path is changed. If the region is formed in most of the region except a part of the minute region, a semiconductor light emitting device having a large emission diameter can be manufactured contrary to each of the above embodiments. Such a semiconductor light emitting device is characterized by a large light emission output (high external light emission efficiency) and a low device resistance. For example, in the semiconductor light emitting device A15 shown in FIGS. 19A and 19B, Be ions are implanted into the central portion of the n-type upper cladding layer 5, and a current is blocked between the ion implantation region 96 and the upper cladding layer 5. A layered pn junction is formed, and a wide current passage region 97 is formed around the ion implantation region 96. An n-side electrode 98 is provided on the upper surface of the cap layer 6 just above the ion implantation region 96, and Be ions are implanted into the multilayer reflective film layer 2 in a region immediately below the current passage region 97. An ion implantation area 99 is formed. Then, the current i flowing from the p-side electrode 100 flows to the n-side electrode 98 through the ion implantation region 99 and the current passage region 97, emits light in a large area of the active layer 4, and a large emission diameter can be obtained. .

Further, in the semiconductor light emitting device A16 shown in FIGS. 20A and 20B, Be is formed in the multilayer reflective film layer 2 in a region directly below the ion-implanted region 96 formed by implanting Be ions in the upper cladding layer 5. Ions are implanted to form the ion implantation region 101. Then, the p-side electrode 1
The current i flowing from 00 flows through the ion implantation region 101 and the current passage region 97 to the n-side electrode 98. At this time, the ion implantation region 96 serving as a current blocking layer prevents the current i from concentrating in the central portion, so that light is emitted in a large area of the active layer 4 and a large emission diameter is obtained.

In each of the above embodiments, AlGa
Although the As-based semiconductor light emitting device has been described, the material of the semiconductor light emitting device of the present invention is not limited to the AlGaAs system. The present invention can be applied not only to the light emitting diode but also to a semiconductor laser device.

Next, application examples using the above semiconductor light emitting device will be described. First, FIG. 21 (a) (b) (c)
The floodlight (light emitting device) B shown in FIG. In this projector B, the semiconductor light emitting device 121 of the present invention is die-bonded on one lead frame 122 and is wire-bonded to the other lead frame 123, and is wire-bonded to the other lead frame 123. It is cast and sealed, and it has a rectangular block-shaped outer shape as a whole. On the surface of the sealing resin 124, a Fresnel type flat plate lens 125 in which a large number of annular lens units are concentrically arranged is integrally formed, and on both sides of the surface, the same height as the Fresnel type flat plate lens 125, or Fresnel. A jaw 126, which is slightly higher than the die flat lens 125, is provided so as to project, and the jaw 126 protects the Fresnel flat lens 125.

In the case of this projector B, the semiconductor light emitting element 12
Since No. 1 has a high luminous efficiency and has a minute luminous region, the Fresnel type flat lens 125 narrows the directional characteristics of light, and the output is strong and a thin beam can be obtained even at a long distance. For example, when the Fresnel type flat lens 125 has a focal length f = 4.5 mm and a lens diameter of 3.5 mm and the light extraction window of the semiconductor light emitting device 121 has a diameter of 20 μm, the beam diameter at a distance of 1 m is about 4 mm. is there. However, in the case of a conventional light emitting diode that has been conventionally used (that is, the light emitting area of which is about 350 μm square), the diameter is 70 mm.
Since it spreads to some extent, a great advantage can be obtained by manufacturing the projector B using the semiconductor light emitting device 121 according to the present invention.

Further, as a light projector Q used conventionally, there is one having a structure as shown in FIG. This is because the semiconductor laser element 323 and the Fresnel type flat lens 32 are attached to the heat sink 322 protruding from the stem 321.
4 is attached, and these are covered with a metal cap 325, which is a can-seal type, but the structure of the floodlight B of the present invention is greatly simplified as compared with such a conventional floodlight Q, and the cost and The bulk volume can be reduced.

Here, although the case where the collimated light beam having a narrow directivity is emitted as the projection beam has been described, by changing the parameters of the Fresnel type flat plate lens 125, the projection beam such as a condensed beam or a deflected beam can also be projected. The applicability is self-evident.

FIG. 22 shows a handy type pointer (light projector) C for pointing the position of an image or the like on a screen or the like. The pointer C is a light emitting diode (LED) 131 according to the present invention, a light projecting lens 132 for collimation, an operating circuit 133 and a battery 13.
The light emitted from the semiconductor light emitting element 131 is collimated by the light projecting lens 132 and then projected onto the screen, and the designated spot is indicated by a light spot.

Most of the pointers currently used are those using a semiconductor laser element, but since laser light is used, it is harmful if the emitted laser light enters the eyes of the surrounding people. Due to this danger, problems such as laser regulation have occurred. Therefore, in order to solve such a problem, an LED pointer using a light emitting diode has been considered. However, in the case of an LED pointer that uses a conventional surface-emitting LED (emission diameter of 400 μm) and is collimated with a projection lens having a focal length f = 10 mm and a lens diameter of 4 mm, the beam diameter on the screen 5 m ahead is 200 mm.
It spreads so much that it becomes almost invisible.

On the other hand, in the case of the pointer C using the LED 131 according to the present invention, the LED having the emission diameter of 10 μm is used.
When 131 and a similar light projecting lens 132 having a focal length f = 10 mm and a lens diameter of 4 mm are used, the beam diameter is as small as 5 mm even on a screen 5 m ahead, which makes it easy to see. Therefore, by improving the light output and directivity with the LED 131 of the present invention, it is possible to manufacture a safe and easy-to-see pointer C.

FIG. 23A is a perspective view showing a transmissive optical rotary encoder D using the semiconductor light emitting device 145 according to the present invention. The rotary encoder D includes a rotary plate 14 attached to a rotary shaft 141.
2. A fixed plate 143 facing the outer peripheral portion of the rotary plate 142, a light projecting lens 144 facing the rotary plate 142 and the fixed plate 143, a semiconductor light emitting element 145 and a light receiving element 146 according to the present invention. . The outer circumference of the rotary plate 142 has slits 14 at intervals of 1 mm over the entire circumference.
7 are perforated, and the fixed plate 143 also has a track A slit 148 and a track B slit 14 at an interval of 1 mm.
9 is perforated.

The light emitted from the semiconductor light emitting element 145 is collimated by the light projecting lens 144,
It is divided by the slits 148 and 149 of the fixed plate 143, passes through the slit 147 of the rotary plate 142, and is detected by the light receiving element 146. Track A slit 148 of the fixing plate 143
The track B slit 149 and the track B slit 149 have their electrical phase angles shifted by 90 °, and both the A phase signal and the B phase signal are ON (light receiving state).
The scale is read by counting when it becomes 1 unit (1 slit) of the scale. Also, FIG.
Turn on from phase A as shown in (b), or B
The direction of rotation can be discriminated by turning on the phase.

In this rotary encoder, for example, a conventional surface-emitting type semiconductor light emitting device (emission diameter 400 μm) is used.
m) and collimating with a projection lens having a focal length f = 10 mm and a lens diameter of 4 mm, the beam diameter on the rotating plate spreads to the slit width of the fixed plate + about 40 μm due to the poor collimating property. . Therefore, 6
With a scale of 00 DPI (40 μm pitch) or more, the beam spreads beyond the slit width, the scale cannot be read, and high resolution cannot be achieved.

On the other hand, in the rotary encoder D using the semiconductor light emitting device 145 according to the present invention, the light emitting diameter of the semiconductor light emitting device 145 can be reduced to about 10 μm, so that the focal length f = 10 mm and the lens diameter 4 mm. Even if collimation is performed using the same light projecting lens 144, the beam diameter on the rotary plate 142 can be suppressed to the slit width of the fixed plate 143 + about 0.5 μm. Therefore, high resolution is possible, and 600
It is also possible to read a scale of DPI (40 μm pitch) or more. Therefore, by using the semiconductor light emitting device 145 according to the present invention for the rotary encoder D,
The resolution of the rotary encoder D can be improved without using a special optical system.

Although the rotary encoder has been described in the above embodiment, the same effect can be obtained by using the semiconductor light emitting device according to the present invention in the linear encoder.

FIG. 24 shows a semiconductor light emitting device 15 according to the present invention.
3 is an explanatory diagram showing a configuration of an optical distance sensor E using 1. The distance sensor E includes a light projecting portion including a semiconductor light emitting device 151 and a collimator lens 152 according to the present invention,
It is composed of a light-receiving lens 153 and a light-receiving section including a position detection element 154.

Further, FIG. 24 shows a case where the step d of the unevenness of the object 155 is measured by the distance sensor E. The light emitted from the semiconductor light emitting device 151 is collimated by the collimator lens 152, and then the object 1
The beam spots SP ₁ and SP ₂ are generated by being irradiated onto 55, and the reflected images of the beam spots SP ₁ and SP ₂ are formed on the position detecting element 154. These image forming positions can be detected by the signal ratios obtained by the signal lines 156 and 157 of the position detecting element 154, and the step d is calculated from the amount of positional deviation using the principle of triangulation.

Since the semiconductor light emitting device 151 according to the present invention has a high output and a limited light emitting region and has a minute light emitting window, the semiconductor light emitting device 151 according to the present invention is used for such a distance sensor E. Thus, long-distance detection is possible, the beam spot diameter is small, and the resolution can be improved.

FIG. 25 shows the measurement result of the step d by the distance sensor E. This is 10c from the distance sensor E
2 mm and 5 mm in height and 2 at a position separated by m
It is a measurement result when an object having concave portions of mm and 5 mm is positioned, and a characteristic curve 158 corresponding to the step d is obtained. In the characteristic curve 158, a is 2 mm.
2 mm, 5 mm convex, 5 mm concave, 2 mm concave
It is a portion corresponding to a recess of mm.

FIG. 26 shows a semiconductor laser device 1 according to the present invention.
It is a perspective view which shows the laser beam printer F using 61. This is a semiconductor laser device 161, a light projecting side collimator lens 162, and a rotary polygon mirror (polygon mirror) 16.
3, a scanner motor 164 for rotating the rotary polygon mirror 163 at a constant speed in a constant direction, and a scanner controller 16
5, a condenser lens 166, a photosensitive drum 167, a horizontal synchronization light receiving sensor 168, and the like.

Thus, the light emitted from the semiconductor laser device 161 passes through the light projecting side collimator lens 162 to become collimated light, which is reflected by the rotary polygon mirror 163 and scanned in the horizontal direction, and is then exposed by the condenser lens 166. The light is focused on the body drum 167 to form a latent image on the photoconductor drum 167.

In such a laser beam printer, for example, a conventional surface emission type LED (emission diameter 400 μm) is used.
m) with a condensing lens with a focal length f = 15 mm
If the light is focused on the photosensitive drum 0 mm ahead, the beam diameter on the photosensitive drum is 4.
It was as large as 8 mm, and could not satisfy the print density specification of 400 DPI.

On the other hand, in the laser beam printer F using the semiconductor laser device 161 according to the present invention,
Since the emission diameter can be reduced to about 5 μm, the beam diameter can be narrowed to 60 μm or less even when the light is condensed under the same conditions, and the specifications of 400 DPI can be sufficiently satisfied.

FIG. 27A is a perspective view showing a bar code reader G using the semiconductor light emitting device 171 according to the present invention. This bar code reader G includes a semiconductor light emitting device 17
1, a light projecting side condenser lens 172, a rotary polygon mirror 173, a scanner motor 174 for rotating the rotary polygon mirror 173 in a constant direction at a constant speed, a constant velocity scanning lens 175, a light receiving side condenser lens 176, and a light receiving element 177. Has been done.

Thus, the light emitted from the semiconductor light emitting element 171 passes through the light projecting side condenser lens 172, is reflected by the rotary polygon mirror 173, is scanned in the horizontal direction, and is made uniform in speed by the constant speed scanning lens 175. After being bar code 17
8 is focused and scanned on the barcode 178. Further, the reflected light from the bar code 178 is condensed and detected on the light receiving element 177 by the light receiving side condensing lens 176, and the bar code signal BS is obtained. In this bar code reader G, since the scanning speed of the light beam is made uniform by the constant speed scanning lens 175, when the horizontal axis represents time and the vertical axis represents the detection signal (bar code signal BS),
As shown in FIG. 27B, the signal BS corresponding to the barcode 178 is obtained.

In such a bar code reader, for example, if a conventional surface-emitting type LED (light emission diameter 400 μm) is used and light is condensed on a bar code 250 mm ahead by a condensing lens with a focal length f = 15 mm, The beam diameter on the bar code is as large as about 6.7 mm due to its poor light condensing property, and the Har code (generally, the minimum line width is 0.2 m
m) cannot be read at all.

On the other hand, in the bar code reader G using the semiconductor light emitting device 171 according to the present invention, the light emitting diameter can be made as small as about 10 μm. The beam diameter on the code 178 can be narrowed down to the minimum line width of the barcode 178 or less (a little less than 0.2 mm), and the barcode 178 can be read.

FIGS. 28A to 28G are schematic views showing optical fiber modules H1 to H7 each comprising a semiconductor light emitting device 181 and an optical fiber 182 according to the present invention. In FIG. 28A, the end surface of the optical fiber 182 faces the light emitting region of the semiconductor light emitting element 181, and the light emitted from the semiconductor light emitting element 181 enters the core from the end surface of the optical fiber 182, Is a direct-coupling type optical fiber module H1. 28B, the semiconductor light emitting element 181 and the end surface of the optical fiber 182 are brought close to each other, and the optical resin 18 is provided between the semiconductor light emitting element 181 and the end surface of the optical fiber 182.
Direct coupling type optical fiber module H2 filled with 3
Is. 28C, 28D, and 28E, a focusing optical system is placed between the semiconductor light emitting element 181 and the end face of the optical fiber 182, and the light emitted from the semiconductor light emitting element 181 is a focusing optical system. The individual lens coupling type optical fiber modules H3 to H5 that are focused and efficiently enter the optical fiber 182, and the optical fiber module H3 of FIG. 28C is used as a focusing optical system for focusing. The rod lens 184 is used, and in the optical fiber module H4 of FIG. 28D, the spherical lens 186 fixed with the resin 185.
28E, the focusing rod lens 184 and the spherical lens 186 are used in the optical fiber module H5 of FIG. The optical fiber modules H6 and H7 shown in FIGS. 28F and 28G have a spherical portion 187 having a lens function at the tip.
The optical fiber (front spherical fiber) 182 provided with is opposed to the semiconductor light emitting element 181 in the fiber lens coupling system.

In such an optical fiber module, the coupling efficiency between the semiconductor light emitting element and the optical fiber strongly depends on the emission diameter of the semiconductor light emitting element. FIG. 29 is a diagram showing the theoretical limit value αc of the coupling efficiency in several types of optical fiber modules of the direct coupling type and the lens coupling type (optical book “Optical Communication Element Engineering” by Hiroo Yonezu). As shown in this figure, it is generally known that the smaller the emission diameter D of the semiconductor light emitting element, the higher the coupling efficiency. Therefore, in order to increase the coupling efficiency of the optical fiber module, it is very effective to reduce the emission diameter of the semiconductor light emitting device.

However, in a conventional semiconductor light emitting device such as an LED, when the light emitting diameter is made small, the device resistance rises, heat is generated intensely, and a large light output cannot be obtained.

On the other hand, in the semiconductor light emitting device (especially LED) 181 having a small light emission diameter according to the present invention, the increase in the element resistance can be suppressed to a low level even if the light emission diameter is made small, so that the light output is lowered. Can be made smaller. Therefore, it is possible to obtain high coupling efficiency without lowering the optical output. In particular, since the semiconductor light emitting device 181 of the present invention uses the AlGaInP-based material for the active layer, it is possible to obtain a high light emitting efficiency even at around 660 nm where the transmission loss of the plastic fiber is minimized.
In an optical fiber communication system using a plastic fiber, a system with low loss and a high SN ratio can be constructed.

FIG. 30 (a) is a schematic view showing an optical fiber type sensor J using the semiconductor light emitting device 191 according to the present invention. This optical fiber type sensor J includes a semiconductor light emitting device 1
91, light projecting optical fiber 192, light receiving optical fiber 19
3, a light receiving element 194 and a processing circuit 195.

Thus, the light emitted from the semiconductor light emitting device 191 is sent through the light projecting optical fiber 192 with a low loss and is emitted from the end face of the optical fiber 192 toward the object 196. The light reflected by the object 196 enters the light receiving optical fiber 193 and is detected by the light receiving element 194. In this way, the output of the light receiving signal detected by the light receiving element 194 changes as shown in FIG. 30B depending on the distance S between the end faces of the optical fibers 192 and 193 for projecting and receiving light and the object 196. The distance S to 196 can be known. In such a sensor, the distance when the received light signal falls to a detectable level is the detectable distance. Therefore, when the semiconductor light emitting device 191 according to the present invention is used, light with a small emission diameter can be emitted, so that the coupling efficiency with the light projecting optical fiber 192 is increased and the light is incident into the light projecting optical fiber 192. Even if the light is increased and the distance S to the detection object 195 is increased, a sufficient detection signal can be obtained, and the detectable distance can be increased.

[0108]

According to the semiconductor light emitting device of the present invention, it is possible to emit light in a minute region of the active layer by means of the current passage region, and it is possible to obtain minute light emission (or a large light emission diameter) with high luminous efficiency. Further, the light reflected by the semiconductor multilayer reflective film layer can also be extracted to the outside, and the external light emission efficiency can be improved. Moreover, since the element resistance can be reduced by making a part of the semiconductor multilayer reflective film layer disordered, the driving voltage of the semiconductor light emitting element can be reduced, and for example, battery driving can be performed. Moreover, since the element resistance is reduced, the thermal saturation of the light output is also reduced, and the light output can be increased.

Therefore, according to the present invention, it is possible to manufacture a semiconductor light emitting device having a small light emission diameter or a large light emission diameter, a very high light emission efficiency, and a low driving voltage.

Further, in the method for manufacturing a semiconductor light emitting device according to the present invention, in the manufacturing process of the semiconductor light emitting device having such characteristics, the disorder of the current passage region (current passage limiting region) and the semiconductor multilayer reflective film layer is achieved. The alignment with the patterned region can be easily performed without alignment, and the manufacturing process can be simplified.

Further, since the semiconductor light emitting element of the present invention has a small light emission diameter and can increase the light output, it can be used in an optical detection device, an optical information processing device, a projector, an optical fiber module, Various optical devices with good performance can be manufactured.

[Brief description of drawings]

1A and 1B are a plan view and a sectional view showing a semiconductor light emitting device according to an embodiment of the present invention.

2 (a), (b), (c) and (d) are cross-sectional views showing a method for manufacturing the semiconductor light emitting device.

3A and 3B are a plan view and a sectional view showing a semiconductor light emitting device according to another embodiment of the present invention.

4A and 4B are a plan view and a cross-sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

5 (a), (b), (c) and (d) are cross-sectional views showing a method for manufacturing the semiconductor light emitting device.

6A and 6B are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

7A and 7B are a plan view and a cross-sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

8A and 8B are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

9 (a), (b), (c) and (d) are cross-sectional views showing a method for manufacturing the semiconductor light emitting device.

10A and 10B are a plan view and a cross-sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

11A and 11B are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

12A and 12B are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

13 (a), (b) and (c) are cross-sectional views showing a method for manufacturing the semiconductor light emitting device.

14A and 14B are a plan view and a cross-sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

15A and 15B are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

16A and 16B are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

17A and 17B are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

18 (a) and 18 (b) are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

19A and 19B are a plan view and a cross-sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

20A and 20B are a plan view and a sectional view showing a semiconductor light emitting device according to still another embodiment of the present invention.

21 (a), (b) and (c) are a perspective view, a horizontal sectional view and a side sectional view showing a projector using the semiconductor light emitting device according to the present invention.

FIG. 22 is a cross-sectional view showing a pointer using a semiconductor light emitting device according to the present invention.

23A is a perspective view showing a rotary encoder using a semiconductor light emitting device according to the present invention, and FIG. 23B is a waveform diagram showing an A-phase signal and a B-phase signal of the encoder.

FIG. 24 is a schematic view showing a configuration of a distance sensor using a semiconductor light emitting device according to the present invention.

FIG. 25 is a diagram showing an example of a measurement result obtained by the distance sensor of the above.

FIG. 26 is a perspective view showing a laser beam printer using a semiconductor light emitting device according to the present invention.

27A is a perspective view showing a bar code reader using a semiconductor light emitting device according to the present invention, and FIG. 27B is a view showing a detection signal by the bar code reader.

FIG. 28 (a) (b) (c) (d) (e) (f)
(G) is a schematic diagram showing various optical fiber modules by the present invention, respectively.

FIG. 29 is a diagram showing the theoretical limit value of the coupling efficiency in the optical fiber module of the direct coupling type and the lens coupling type.

FIG. 30 (a) is a schematic diagram showing the configuration of an optical fiber type sensor, and FIG. 30 (b) is a diagram showing a change in received light output depending on the distance to an object.

FIG. 31 is a partially cutaway perspective view showing a structure of a conventional semiconductor light emitting device.

FIG. 32 is a partially cutaway perspective view showing a conventional light projector.

[Explanation of symbols]

 A1 to A16 semiconductor light emitting element 1,21,41 GaAs substrate 2,25,45 multilayer reflective film layer 4,23,43 active layer 8,28 ion-implanted region (disordered region) 9,29 ion-implanted region 10, 30 current passage region 12, 32 n-side electrode 36 impurity diffusion region 47 current blocking layer 50 Zn diffusion region 51 current passage region 52 ion implantation region B light projector C pointer D rotary encoder E distance sensor F laser beam printer G barcode reader H1 H7 Optical fiber module J Optical fiber type sensor

Claims (18)

[Claims] 1. A semiconductor light emitting device having an active layer and a semiconductor multilayer reflective film layer, wherein a part of the semiconductor multilayer reflective film layer is disordered, and a current path region serving as a path for a current injected into the active layer is formed. A semiconductor light emitting device, characterized in that a current path limiting means for limiting is provided. 2. The semiconductor light emitting device according to claim 1, wherein the semiconductor multilayer reflective film layer has a conductivity type of p type. 3. The semiconductor light emitting device according to claim 1, wherein an electrode is formed on the entire upper surface of the device except for most of the current passage region. 4. The semiconductor light emitting device according to claim 1, wherein the semiconductor multilayer reflective film layer is disordered except for most of the region just above or below the current passage region. . 5. The semiconductor light emitting device according to claim 4, wherein the area of the non-disordered region of the semiconductor multilayer reflective film layer and the area of the current passage region are substantially equal to each other. 6. The semiconductor light emitting device according to claim 1, wherein the semiconductor multilayer reflective film layer is disordered in most of the portion just above or below the current passage region. 7. The semiconductor light emitting device according to claim 6, wherein the area of the disordered region of the semiconductor multilayer reflective film layer and the area of the current passage region are substantially equal to each other. 8. The semiconductor light emitting device according to claim 1, wherein the semiconductor multilayer reflective film layer is a current path limiting layer. 9. A step of forming a wafer having a double hetero structure having a semiconductor multilayer reflective film layer, and a step of introducing an impurity into a predetermined position of the wafer using a mask to form or limit a current passage region, A method of manufacturing a semiconductor light emitting device, comprising the step of disordering a part of the semiconductor multilayer reflective film layer by introducing impurities to a depth reaching at least the semiconductor multilayer reflective film layer using the mask of. 10. The method for manufacturing a semiconductor light emitting device according to claim 9, wherein the method of introducing impurities to a depth reaching the semiconductor multilayer reflective film layer is a diffusion method. 11. The method for manufacturing a semiconductor light emitting device according to claim 9, wherein the method of introducing the impurities to a depth reaching the semiconductor multilayer reflective film layer is an ion implantation method. 12. The method of manufacturing a semiconductor light emitting device according to claim 9, wherein the impurities introduced into the semiconductor multilayer reflective film layer are zinc or beryllium. 13. A step of forming a wafer having a semiconductor multilayer reflective film layer and at least one pn junction semiconductor layer above an active layer, a step of forming a solid phase diffusion source on the wafer, and a step of forming the diffusion source. A method of manufacturing a semiconductor light emitting device, comprising: a pn junction semiconductor layer formed above an active layer and a step of diffusing until penetrating a semiconductor multilayer reflective film layer. 14. A step of forming a wafer having at least one pn junction semiconductor layer above a semiconductor multilayer reflective film layer and an active layer, a step of forming a solid phase diffusion source on the wafer, and a step of forming the diffusion source. And a step of performing diffusion until it penetrates a pn junction semiconductor layer formed above the active layer, and performing ion implantation at least to a depth reaching the semiconductor multilayer reflective film layer using this solid-phase diffusion source as a mask. Method for manufacturing semiconductor light emitting device. 15. The light source according to claim 1, 2, 3, 4,
An optical detection device characterized by using the semiconductor light emitting device described in 5, 6, 7 or 8. 16. The light source according to claim 1, 2, 3, 4,
An optical information processing device comprising the semiconductor light emitting device described in 5, 6, 7 or 8. 17. The light source according to claim 1, 2, 3, 4,
A light projector using the semiconductor light emitting device described in 5, 6, 7 or 8. 18. The light source according to claim 1, 2, 3, 4,
An optical fiber module using the semiconductor light emitting device described in 5, 6, 7 or 8.