JPH05304332A - Optical semiconductor device - Google Patents

Abstract

PURPOSE:To prolong service life by introducing at least one kind of impurities, selected from group III and V elements other than the main elements of group III and V constituting the active layer of a semiconductor layer, into the semiconductor layer having at least an active layer. CONSTITUTION:A first clad layer 12 composed at least of AlX1GaY1In1-X1-Y1P, an active layer 13 composed of AlX2GaY2In1-X2-Y2P, and a second clad layer 14 composed of AlX3GaY3In1-X3-Y3P are laminated sequentially, with lattice being matched, on a semiconductor substrate 11 composed of GaAs. At least one kind of element selected from B, N As, Sb is added, as impurities, to the semiconductor layer containing at least the active layer 13. Similarly, at least one kind of element selected from B, Al, N or Sb in case of InGaAs system while selected from B, In, N or P in case of A GaAsSb system is introduced, as impurities, into a semiconductor layer containing at least an active layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical semiconductor device, and more particularly, to a semiconductor laser device and a light emitting diode (LED) with little deterioration in characteristics relating to life.

[0002]

2. Description of the Related Art There are mainly the following three modes of deterioration of characteristics of a conventional optical semiconductor device.

(A) Catastrophic optical damage (COD) (B) End surface deterioration (C) Dark line / dark spot deterioration Among these, (A) and (B) are end surface emitting type optical semiconductor devices,
Particularly, it is peculiar to the semiconductor laser device, and (C) is a time-dependent characteristic variation mode existing in both the semiconductor laser device and the LED. Among these deterioration modes, a window stripe type structure has been developed for catastrophic optical damage. Regarding end face deterioration, a technique has been developed to prevent end face deterioration by preventing surface oxidation by forming an end face protective film. Regarding the dark line and dark spot deterioration, care was taken not to introduce unnecessary impurities as much as possible in the crystal growth process and the wafer process. Further, elements of the groups 3 and 5 other than the main elements of the groups 3 and 5 configured to control the lattice constant and the band gap are not positively introduced as impurities. That is, in the case of the AlGaInP optical semiconductor device, elements of groups 3 and 5 other than Al, Ga, In, and P are not introduced as impurities. Similarly, I
In the case of an nGaAsP-based optical semiconductor device, In, Ga, A
Group 3 and 5 other than s and P, Al in the case of AlGaAsSb-based semiconductor devices, group 3A and 5A other than Ga, As, Sb, and I in the case of InGaAsSb-based optical semiconductor devices.
Groups 3 and 5 other than n, Ga, As, and Sb, AlGaA
In the case of the s-based optical semiconductor device, elements of groups 3 and 5 other than Al, Ga and As are not positively introduced as impurities.

As an example of the long-term reliability evaluation result of the conventional optical semiconductor device, AlGaInP is shown in FIGS. 7, 8 and 9, respectively.
2 shows life characteristics of a semiconductor laser device, an InGaAsP semiconductor laser device, and an AlGaAs semiconductor laser device. Here, the conditions of the life test are as follows: AlGaInP optical semiconductor device, ambient temperature Ta = 50 ° C., optical output P = 5 m
Energization was performed at W, and the operating current Iop was measured under the conditions of Ta = 25 ° C. and P = 5 mW. Similarly, InGa
In case of AsP semiconductor device, Ta = 70 ° C., P = 5
Power is supplied at mW, and Iop is measured at Ta = 25 ° C.
Performed at P = 5 mW. In the case of an AlGaAs optical semiconductor, energization is performed at Ta = 70 ° C. and P = 5 mW,
The Iop was measured at Ta = 25 ° C. and P = 5 mW.

[0005]

In the conventional optical semiconductor device described above, dislocations and crystal defects move in the crystal during operation,
At that time, non-radiative recombination centers (so-called dark lines and dark spots) increase, and as a result, there is a drawback that the electro-optical characteristics have a variation with time. In particular, it has a short life due to deterioration of dark lines and has a drawback that long-term reliability is not sufficient. Further, even when the long-term reliability has reached a level at which there is no practical problem, there is a drawback that the yield in the energization screening step is low or unstable.

[0006]

In the optical semiconductor device of the present invention, a semiconductor layer including at least an active layer is doped with an element of a group 3 or 5 other than the main elements of the group 3 or 5 constituting the active layer. As at least one type is introduced.

That is, specifically, in the case of AlGaInP system, at least one element of B, N, As, and Sb is introduced into a semiconductor layer including at least an active layer. Similarly, in the case of InGaAsP system,
At least one element selected from B, Al, N, and Sb
In the case of AlGaAsSb system, at least one kind of element of B, In, N, P, in InGaAsSb system, at least one kind of element of B, Al, N, P, and in case of AlGaAs system At least P is introduced as an impurity into a semiconductor layer including at least an active layer.

[0008]

First, the principle of the present invention will be described.

Among the characteristic deterioration modes of conventional optical semiconductor devices, for example, semiconductor laser devices, dark line deterioration or dark spot deterioration is one that has the longest effect on life. Further, one of the processes having the lowest yield and unstable yield among the conventional manufacturing and sorting processes for optical semiconductor devices is the screening screening process, which is caused by the dark line deterioration and dark spot deterioration. .. That is, if the dark lines and dark spots are suppressed from being deteriorated, the yield of the manufacturing and sorting process is remarkably improved and stabilized, and the life of the optical semiconductor device is remarkably improved.

The deterioration of dark lines and dark spots is that crystal defects or dislocations move in the crystal during the operation of the optical semiconductor device to increase non-radiative recombination regions (so-called dark lines and dark spots). is there. This means that conversely, if the movement of crystal defects and dislocations is stopped, the increase of the non-radiative recombination region can be suppressed. The main point of the present invention is exactly at this point, and pays attention to the movement of crystal defects and dislocations in the semiconductor crystal, and introduces into the semiconductor crystal a mechanism that prevents them from moving.

Let us now consider the movement of dislocations in a semiconductor crystal. Generally, a force vector F acting on dislocations in the crystal
Is expressed as the following equation using the stress tensor a _hl in the crystal and the tensor d _{hl of the} dislocation moment, where i is the component in the i direction.

[0012]

Here, X _i represents the i-direction component of the position vector.

Equation (1) is

[0015]

That is, it is shown that the force does not act on the dislocations in a uniform stress field, and the force acts on the dislocations.

[0017]

That is, it means only when the local stress field exists. When Fi> 0, a repulsive force acts between the dislocation and the local stress field, and when Fi <0, an attractive force acts.

Next, in order to prevent dislocations from moving due to the effect of the local stress field, (A) an attractive force acts between the dislocation and the local stress field.

(B) The local stress field itself does not move (or the moving speed is extremely slow).

It is necessary to satisfy the above two conditions at the same time. At this time, dislocations are expected to be pinned by the local stress field and not move.

It is known that a local stress field is generated in the vicinity of impurities introduced into a semiconductor crystal.
Given this, let us consider the interaction between dislocations and the local stress field due to impurities introduced into the crystal.
The local stress field due to impurities introduced in the crystal

[0023]

In the case of, Fi can be positive or negative depending on the positional relationship between the local stress field and the dislocation. That is, there is a case where a repulsive force or an attractive force acts at the same probability between a specific local stress field and a dislocation. Of these, when attractive force acts, the dislocation is pinned, while when repulsive force acts, the dislocation moves. In this dislocation that has moved, the attractive force and the repulsive force may act with the same probability in the same way as the local stress field that will be encountered next. As this is repeated, the dislocations are pinned by the local stress fields scattered in the crystal. This is

[0025]

The same applies to the case of. In contrast, there is no local stress field

[0027]

In the case of (1), no force acts on the dislocation, and the dislocation moves without changing its own moving speed. These means that what is important for pinning dislocations is not the positive or negative of the local stress field tensor, but the absolute value of the local stress field tensor.

Similarly, considering the interaction between the point defect in the crystal and the local stress field, in the case of a vacancy,

[0030]

An attractive force acts between the local stress field and

[0032]

A repulsive force acts between the local stress field and On the other hand, for interstitial defects

[0034]

An attractive force acts between the local stress field and

[0036]

A repulsive force acts between the local stress field and Considering that not only Schottky defects but also Frenkel defects exist in the semiconductor crystal, it is desirable that both vacancy and interstitial defect can be pinned. That is,

[0038]

And the local stress field

[0040]

So that there are both local stress fields
It is desirable to introduce two or more kinds of impurities into the semiconductor crystal.

Next, the conditions of impurities effective for pinning dislocations and crystal defects are considered.

First, let us consider the moving speed of the local stress field, assuming that the local stress field is due to impurities in the crystal. Impurities in crystals are roughly classified into substitutional impurities and interstitial impurities. As is well known, between substitutional impurities and interstitial impurities, interstitial impurities generally have a higher diffusion rate. From this, it is expected that the local stress field due to substitutional impurities will have a slower moving speed than the local stress field due to interstitial impurities. Therefore, the first is required as an impurity that produces a local stress field that is effective in pinning dislocations.
The condition is that it is a substitutional impurity.

Next, let us consider the restriction due to the change in the electrical characteristics of the semiconductor crystal caused by the addition of impurities. In general, semiconductors control the electrical characteristics by introducing impurities that form a donor level or an acceptor level. Here, if the impurities introduced to pin the movement of dislocations seem to form a donor level or an acceptor level, the original electrical characteristics are affected, which is not useful. Therefore, the condition of an impurity that is practically useful for suppressing the movement of dislocations is that it is an element belonging to the same group as the constituent semiconductor crystal. For example, in the case of a Group 3-5 semiconductor, the Group 3 or Group 5 element does not affect the electrical characteristics of the semiconductor, and is practically useful as an impurity introduced to suppress the movement of dislocations.

Next, the local stress field formed by these impurities will be considered. It is assumed that a substitutional impurity is introduced into a semiconductor crystal having a lattice constant a ₀ . At this time, the lattice constant originally formed by the substitutional impurity with the adjacent element in the crystal in the X _i direction with respect to the origin of the impurity position is a _i . In the case of a mixed crystal type semiconductor, there are some a _i instead of one. a
_In the case of an impurity introduced at a position such that _i > a ₀ ,
With the position of this impurity as the origin, in the X _i direction

[0046]

A local stress field of On the other hand, a _i <a ₀
In the case of impurities introduced at the position where

[0048]

A local stress field of And (a _i −
The magnitude of a ₀ ) / a ₀ is

[0050]

The size of is determined.

Based on the above discussion of the local stress field, let us consider the local stress field existing in the 3-5 group mixed crystal semiconductor itself.

Table 1 is a list of lattice constants of 3-5 group semiconductors. Of these, those in which the values of a and c are entered indicate that they have a WURZITE crystal structure, and the others have a zinc blend (ZINCBLENDE) crystal structure.

[0054]

[Table 1]

Here, the relationship between the fluctuation of the lattice constant in the crystal and the dark line deterioration will be discussed by taking some 3-5 group mixed crystal semiconductor laser devices as an example.

As an example, an AlGaAs-based semiconductor laser device crystal-grown on a GaAs substrate and an AlGaInP-based semiconductor laser device crystal-grown on a GaAs substrate,
An InGaAsP-based semiconductor laser device crystal-grown on an InP substrate will be compared. First, in the case of Al _X Ga _1-X As crystal grown on a GaAs substrate, the combination of adjacent elements in the crystal is GaAs and AlAs. GaA
The lattice constant a of s _GaAs is 0.5654 nm, while A
lattice constant a _AlAs of lAs is 0.5662Nm. Therefore, the fluctuation of the lattice constant in the Al _X Ga _1-X As mixed crystal is (a _GaAs −a _GaAs ) / a _GaAs = 0%, (a _AlAs −
a _GaAs ) / a _GaAs = 0.14%. This is Al
This means that the local stress field existing in the GaAs mixed crystal itself is very small.

Next, AlGaIn lattice-matched to GaAs
Consider the case of P mixed crystal. Now this AlGaI
The lattice constant a _{AlGaInP of} nP is 0.5654 nm.
On the other hand, the combination of adjacent elements in the crystal is AlP, G
aP and InP. According to Table 1, the lattice constants originally intended to be formed by these combinations of semiconductors are a
_AlP = 0.546 nm, a _GaP = 0.451 nm, a
_InP = 0.5869 nm. The difference in lattice constant between these and the AlGaInP mixed crystal lattice-matched with GaAs (a _i −a _AlGaInP ) / a _AlGaInP is −3.4%, respectively.
It is -3.6% and + 3.8%. That is, AlGaI
In the case of nP mixed crystal, the average lattice constant of the crystal a _AlGaInP
There is a difference of −3.6 to + 3.8% between the lattice constant a _i and the lattice constant a _i originally formed by the combination of the adjacent elements. Due to this difference in lattice constant, AlGa
It is considered that a local stress field is generated in the InP mixed crystal.

Furthermore, InGaA lattice-matched to InP
Considering the case of sP mixed crystal in the same way, a
_{For InGaAsP} = 0.5869 nm, a _InP = 0.58
69 nm, a _InAs = 0.6058 nm, a _GaAs = 0.5
654 nm and a _GaP = 0.5451 nm. From these values, (a _i −a _InGaAsP ) / a _InGaAsP respectively,
It is 0%, + 3.2%, -3.7%, and -7.1%. That is, in the case of InGaAsP mixed crystal, -7.1～ between the lattice constant a _i to be originally formed by the combination of the elements adjacent to the average lattice constant _AInGaAs P crystals + 3.2
%, AlGaInP locally in the crystal
It is considered that there is a local stress field larger than the system.

Comparing the AlGaAs mixed crystal, the AlGaInP mixed crystal, and the InGaAsP mixed crystal based on the above discussions, it is considered that the local stress field is small in the AlGaAs mixed crystal, whereas the AlGaInP mixed crystal and the InGaAsP mixed crystal are considered to be small.
It is considered that there are many local stress fields in the mixed crystal. Therefore, the AlGaAs mixed crystal is more AlGaIn
It is expected that dislocations and crystal defects are more likely to move than in P mixed crystal and InGaAsP mixed crystal, and a failure mode due to dark line deterioration is likely to occur. In fact, dark line deterioration is often found in AlGaAs-based semiconductor lasers, whereas dark line deterioration is relatively rare in AlGaInP-based or InGaAsP-based semiconductor laser devices.

When a substitutional impurity is introduced into a semiconductor crystal having a lattice constant a ₀ , the substitutional impurity is supposed to have a lattice constant a _i originally formed with an adjacent element in the crystal. Above I
The average difference between a ₀ and a _{i in} the case of nGaAsP system is about 3
%. That is, it means that the movement of dislocations and crystal defects can be sufficiently suppressed if there is a difference of at least about 3%. Next, consider the upper limit of the difference between a ₀ and a _i . Hume Rosary in substitutional solid solution
-Rothery) condition, a large solid solubility can be obtained when the difference in lattice constant between the two types of crystals is within about 15%.
It is considered that a difference in lattice constant of about 5 to 30% is allowed. From the above, as the condition of the substitutional impurities for introducing the dark line deterioration into the crystal, (a _i −a ₀ ) / a
It is considered that ₀ may be ± 3 to ± 30%. In addition,
The amount of this impurity introduced can be at least within a range that does not cause lattice mismatch with the substrate semiconductor.

Based on the above discussion, the following combinations can be considered as impurities for suppressing dark line deterioration. That is, in the case of AlGaInP mixed crystal lattice-matched with GaAs, In lattice-matched with B, N, As, Sb, InP
In the case of GaAsP mixed crystal, B, Al, N, Sb, Ga
In the case of AlGaAsSb mixed crystal lattice-matched to Sb,
InGaA lattice-matched to B, In, N, P and InAs
In the case of sSb mixed crystal, B, I, in the case of AlGaAsSb mixed crystal lattice-matched to B, Al, N, P and InP.
GaInAsSb lattice-matched to n, N, P and GaSb
In the case of mixed crystal, B, Al, N, P, InGaAs in the case of AlGaAs mixed crystal grown on a GaAs substrate, In, Sb,
B, N, P are conceivable. Of these impurities,
For the WURZITE type,
It is considered that when it is introduced into the above mixed crystal, it is substituted at the position of Group 5, and the Wurzite type lattice constant a
Was compared with √2 for comparison.

[0062]

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

FIG. 1 is a perspective view showing a first embodiment of the present invention, which is an example applied to an AlGaInP semiconductor laser device. As shown in FIG. 1, 11 is a semiconductor substrate made of n-type GaAs, and 12 is n-type Al _X1 Ga _Y1 In _1-X1-Y1.
First clad layer made of P, 13 is Al _X2 Ga _Y2 In
_1-X2-Y2 P active layer, 14 is p-type Al _X3 Ga _Y3 I
Second cladding layer made of n _{1 -X3-Y3} P, 15 is p-type G
a cap layer made of aAs, 16 is p-type Al _X3 Ga _Y3 I
7 shows a buried layer made of n _{1 -X3-Y3} P for current narrowing, where 17 and 18 are electrodes and back electrodes, and 19 respectively.
Indicates a surface protective film formed on the end surface to prevent deterioration of the end surface. Here, in the present invention, what is particularly important is
This is to introduce at least one element of B, N, As, and Sb into the active layer 13 or the semiconductor layer including the active layer 13 and the clad layers 12 and 14. In the present embodiment, the active layer 13 is Sb was introduced.

FIG. 2 shows the life evaluation results of this embodiment.
The life test is performed at Ta = 50 ° C. and P = 5 mW, and I
The measurement of op was performed at Ta = 25 ° C. and P = 5 mW.
Here, not only is there no deteriorated element, but the operating current I
Almost no increase in op with time is observed.

FIG. 3 is a diagram showing a second embodiment of the present invention, which is an example applied to an InGaAsP semiconductor laser device. As shown in FIG. 3, 31 is a semiconductor substrate made of n-type InP, 32 is a first clad layer made of n-type InP, 33 is an active layer made of In _X4 Ga _1-X4 As _Y4 P _1-Y4 , 34 Is a second cladding layer made of p-type InP, 35
Is a cap layer made of p-type In _X20 Ga _1-X20 As _Y20 P _1-Y20 , 36 is a buried layer made of p-type InP for current narrowing, and 37 and 38 are electrodes and back electrodes, respectively. .. Here, what is particularly important in the present invention is to introduce at least one element of B, Al, N and Sb into the active layer or the semiconductor layer including the active layer and the clad layer. In the example, Sb was introduced into the active layer 33.

FIG. 4 shows a life evaluation result of the second embodiment. In the life test, energization was performed at Ta = 70 ° C. and P = 5 mW, and Iop measurement was performed at Ta = 25 ° C. and P = 5 mW. Here, the increase in operating current Iop with time, which has been observed in the conventional InGaAsP-based semiconductor laser device, is hardly observed.

FIG. 5 is a diagram showing a third embodiment of the present invention, which is an example applied to an AlGaAs semiconductor laser device. As shown in FIG. 5, 51 is a semiconductor substrate made of n-type GaAs, 52 is a first cladding layer made of n-type Al _X17 Ga _{1 -X17} As, 53 is an active layer made of Al _X18 Ga _{1 -X18} As, 54 is a second cladding layer made of p-type Al _X19 Ga _{1 -X19} As, 55 is a cap layer made of n-type GaAs, 56 is a Zn diffusion region for current narrowing, 5
The convex portion 7 indicates an optical guide region formed in the first cladding layer, 58 and 59 are electrodes and back electrodes, respectively.
Reference numeral 60 denotes a surface protective film formed on the end surface to prevent deterioration of the end surface. Here, P is introduced as an impurity into the active layer 53.

FIG. 6 shows a life evaluation result of the third embodiment. The life test was conducted at Ta = 70 ° C. and P = 5 mW, and the Iop was measured at Ta = 25 ° C. and P = 5 mW. Here, almost no increase in the operating current value Iop observed with the AlGaAs semiconductor laser device with time is observed.

The effects described above can be obtained not only in the semiconductor laser device but also in other optical semiconductor devices such as LEDs.

[0070]

As described above, the optical semiconductor device of the present invention has the features described in items 1 to 7 below. That is, (1) AlGa formed by lattice matching with a GaAs substrate
B, N, A as impurities in the InP optical semiconductor device
An optical semiconductor device, wherein at least one or a plurality of elements of s and Sb are introduced into a semiconductor layer including at least an active layer.

(2) In an InGaAsP-based optical semiconductor device which is lattice-matched to an InP substrate, at least one kind of B, Al, N, and Sb, or a plurality of kinds of elements as impurities, at least the active layer. An optical semiconductor device characterized by being introduced into a semiconductor layer including.

(3) In an AlGaAsSb-based optical semiconductor device configured to be lattice-matched to a GaSb substrate, a semiconductor in which at least one element or a plurality of elements of B, In, N, and P as impurities contains at least an active layer. An optical semiconductor device characterized by being introduced into a layer.

(4) In an InGaAsSb-based optical semiconductor device configured to be lattice-matched to an InAs substrate, a semiconductor in which at least one element or a plurality of elements of B, Al, N, and P as an impurity includes at least an active layer. An optical semiconductor device characterized by being introduced into a layer.

(5) In an AlGaAsSb-based optical semiconductor device configured to be lattice-matched to an InP substrate, a semiconductor in which at least one or more kinds of elements of B, In, N, and P as impurities contain at least an active layer. An optical semiconductor device characterized by being introduced into a layer.

(6) In a GaInAsSb-based optical semiconductor device which is lattice-matched to a GaSb substrate, a semiconductor in which at least one or more elements of B, Al, N, and P as impurities contain at least an active layer. An optical semiconductor device characterized by being introduced into a layer.

(7) In an AlGaAs optical semiconductor device configured to be lattice-matched with a GaAs substrate, at least one kind or more kinds of elements of B, In, N, P, and Sb as impurities are used in at least the active layer. Semiconductor device including.

In the optical semiconductor device of the present invention described in the above items 1 to 7, the movement of dislocations and crystal defects in the crystal can be suppressed by the influence of the local stress field introduced into the crystal, and as a result, the life is long. Can be obtained. It also has the effect of improving the yield of the manufacturing process including the screening process related to the life.

[Brief description of drawings]

FIG. 1 is a diagram showing a perspective view of a first embodiment of an optical semiconductor device of the present invention.

FIG. 2 is a diagram showing a life evaluation result of the first embodiment of the optical semiconductor device of the present invention.

FIG. 3 is a diagram showing a perspective view of a second embodiment of an optical semiconductor device of the present invention.

FIG. 4 is a diagram showing a life evaluation result of a second embodiment of the optical semiconductor device of the present invention.

FIG. 5 is a diagram showing a perspective view of a third embodiment of an optical semiconductor device of the present invention.

FIG. 6 is a diagram showing a life evaluation result of an optical semiconductor device according to a third embodiment of the present invention.

FIG. 7 is a diagram showing a life evaluation result of a conventional optical semiconductor device (AlGaInP-based semiconductor laser device).

FIG. 8 is a diagram showing a life evaluation result of a conventional optical semiconductor device (InGaAsP-based semiconductor laser device).

FIG. 9 is a diagram showing a life evaluation result of a conventional optical semiconductor device (AlGaAs semiconductor laser device).

[Explanation of symbols]

11 semiconductor substrate made of GaAs 12 first clad layer made of Al _X1 Ga _Y1 In _1-X1-Y1 P 13 made of Al _X2 Ga _Y2 In _1-X2Y2 P and Sb
Introduced active layer 14 Al _X3 Ga _Y3 In _{1 -X3-Y3} P second cladding layer 15 GaAs cap layer 16 Al _X3 Ga _Y3 I ₁ -X3 _-Y3 P buried layer 17,37 , 58 electrode 18, 38, 59 back electrode 19, 60 surface protection film 31 semiconductor substrate made of InP 32 first clad layer made of InP 33 In _X4 Ga _1-X4 As _Y4 P _1-Y4 , Sb introduced have been the second cladding layer 35 made of the active layer _{34 InP in X20 Ga 1-X20} As Y20 P 1-Y20 consisting cap layer 36 InP consisting of buried layer 51 semiconductor substrate 52 made of GaAs Al _X17 Ga _1-X17 As cap layer 5 made of the first cladding layer 53 Al _X18 Ga _1-X18 consisting As active layer 54 Al _X19 Ga _1-X19 As kana comprising second cladding layer 55 GaAs made more Zn diffusion region 57 the light guide region

Claims (7)

[Claims] 1. At least Al _X1 Ga _Y1 In provided on a semiconductor substrate made of GaAs so as to be lattice-matched and sequentially laminated.
_{A first} glad layer of _1-X1-Y1 P and Al _X2 Ga _Y2
An active layer of In _{1-X2-Y 2} P, and Al _X3 Ga _Y3 In
_In a photosemiconductor device having a second cladding layer made of _{1-X3-Y3P, the} semiconductor layer including at least the active layer contains at least one element of B, N, As, and Sb as an impurity. An optical semiconductor device characterized by the above. 2. A first substrate made of at least InP provided on a semiconductor substrate made of InP so as to be lattice-matched and sequentially laminated.
In the optical semiconductor device having the clad layer, the active layer made of In _X4 Ga _{1 -X4} As _Y4 P _{1 -Y4,} and the second clad layer made of InP, at least the semiconductor layer containing the active layer has B, Al. , N, Sb containing at least one or more elements as impurities. 3. At least Al _X5 Ga _{1 -X5} As _Y5 provided in a lattice-matched laminated order on a semiconductor substrate made of GaSb.
_First clad layer made of Sb _1-Y5 and Al _X6 Ga _1-X6 A
s _Y6 Sb _1-Y6 active layer and Al _X7 Ga _1-X7 As _Y7 Sb
_In a photosemiconductor device having a second clad layer made of _1-Y7 , at least the semiconductor layer including the active layer has B,
An optical semiconductor device comprising at least one element selected from In, N and P as an impurity. 4. At least In _X8 Ga _{1 -X8} A provided on a semiconductor substrate made of InAs so as to be lattice-matched and sequentially laminated.
s _Y8 Sb _1-Y8 first cladding layer and In _X9 Ga
_1-X9 As _Y9 Sb _1-Y9 active layer and In _X10 Ga
_1-X10 As _Y10 Sb _1-Y10 and a second clad layer, wherein the semiconductor layer including at least the active layer contains at least one of B, Al, N, and P.
An optical semiconductor device, which comprises more than one kind of element as an impurity. 5. At least Al _X11 Ga _{1 -X11} As provided on a semiconductor substrate made of InP in a lattice-sequential manner.
First cladding layer composed of _Y11 Sb1 _-Y11 and Al _X12 G
a _1-X12 As _Y12 Sb _1-Y12 active layer and Al _X13
In a photosemiconductor device having a second cladding layer made of Ga _1-X13 As _Y13 Sb _1-Y13 , at least one element selected from B, In, N and P is added to the semiconductor layer including at least the active layer. An optical semiconductor device comprising an impurity. 6. At least Ga _X14 In provided on a semiconductor substrate made of GaSb in a lattice-matched manner and sequentially laminated.
_1-X14 As _Y14 Sb _1-Y14 first clad layer, Ga _X15 In _1-X15 As _Y15 Sb _1-Y15 active layer, Ga _X16 In _1-X16 As _Y16 Sb _1-Y16 In an optical semiconductor device having a second cladding layer,
The semiconductor layer including at least the active layer is provided with B, Al, N,
An optical semiconductor device comprising at least one element of P as impurities. 7. A layer of at least Al _X17 Ga formed on a semiconductor substrate made of GaAs in a lattice-matched manner and sequentially laminated.
_1-X17 As first cladding layer and Al _X18 Ga
_1-X18 As active layer and Al _X19 Ga _1-X19 As
An optical semiconductor device having a second cladding layer made of, wherein the semiconductor layer including the active layer contains at least P as an impurity.