JPS59171186A - Semiconductor light emitting device - Google Patents

Abstract

PURPOSE:To prevent mirror breakdown and thus contrive to stabilize the characteristic and improve the reliability by forming a window layer in accordance with the structure of a quantum well. CONSTITUTION:Under mentioned each layer 12-15 is successively formed on an N type GaAs substrate 11. An N type GaAs buffer layer 12 has the impurity concentration equal to that of the substrate 11, and an N type AlxGa1-xAs clad layer 13 has a forbidden band width larger than that of a well layer 14. The structure of a quantum well 14 is formed by alternately laminating e.g. well layers and barrier layers both in non-doping by means of GaAs for the well layer and AlxGa1-xAs for the barrier layer. By the way, the thickness of the well layer should be a de Broglie's wave length. A P type AlxGa1-xAs clad layer 15 is the same as the layer 13. In this constitution, the light generated in the well layer is confined in the layers 13 and 15 and then go toward a resonance mirror plane M caused by cleavage. The mirror plane M has the forbidden band width increased more than in the well layer, thus obtaining the effect of a window region.

Description

[Detailed Description of the Invention] 1Hi) Technical Field of the Invention The invention relates to a semiconductor light emitting device, particularly an active region of a quantum well (Quan-Well) structure, and a semiconductor light-emitting device that has an active region of a quantum well (K-well) structure and a quantum well (K-well) structure. A selectively applied window region is formed on the semiconductor laser provided with the window region.

(1)) Background of technology 16 What is the use of light in various industrial and consumer fields? In a system that uses f-reporting (2i ginnohe), '4 conductor generating device 6. Ipfeng is also a heavy component, and the actual behavior of the waves and the power of the waves, stable fundamental zero-order transverse mode oscillation, and single 〇) longitudinal mode oscillation 1.
The original beam divergence angle is small, the threshold value is low, and the threshold value is low.
Many efforts have been made to improve timekeeping performance, to improve the force characteristics of direct expansion, to increase the cutting edge, and to reduce the temperature dependence of these characteristics. However, in particular, stability of properties and large lumps of long life are essential.

For this purpose, many semiconductor light emitting devices, especially lasers, have been proposed up to now, one of which is the quantum Tsukido semiconductor laser.

Quantum well (Quantum well)
,) -'l' L9 salary 1---Ij is the thickness of the active layer of the double heterostructure as carrier 117) DouφBlowey wavelength λd (λ” knee for Ga 8) 30f-no
IJ) The active layer is h;: 9 J
It functions as a Y-shaped potential and becomes a two-dimensional electronic state in which the motion of carriers in the J'P direction is numbered. Quantum force negative - Ij - ζ This is a single QuantturnW composed of 11 (Laur layer) as an active one.
ell L/-The, M in which well layers and barrier layers are alternately stacked, ulti Quantum ~ Vel
There is such a thing as l racer 0-dago racer j1.・-Sa0) As for the characteristics, B) b) The characteristics of the old '- style j+1λ degree'J゛0
is passed through θ) tuple heteroleri′ (larger than this,
The stability of the threshold current with respect to temperature -L rises (U) 1 ψ, -' motor oscillation or chanting. →
'iIi Okishiichiku output size-4:j:'s direct ice cream- is good.

(d) Imitation if child effect: AT Yu is trading. The width of the middle well and the burr γQ) city! This makes it possible to design the oscillation wavelength over a wide range.We are looking forward to contributing to the advancement of semiconductor light emitting devices mentioned earlier.

Well, half a cup - one of the deterioration over time of the characteristics of sa (
This deterioration or destruction of the mirror surface of the optical resonator is particularly noticeable when the areal density of the laser beam is high, and one of the phenomena is that the semiconductor forming the mirror surface is attacked by oxygen (02) or water vapor (H, 0) in the atmosphere, forming oxides, etc. - The Ui surface is roughened and the reflectance decreases, resulting in an increase in threshold current and a decrease in laser output, and in severe cases. oscillation becomes impossible.

This deterioration phenomenon becomes a particular problem when the semiconductor is a compound containing aluminum (Aj). Another deterioration phenomenon is that crystal dislocation occurs on the mirror surface, and this extends to the inside of the semiconductor, causing the same characteristic deterioration as described above.

With regard to semiconductor lasers with conventional structures, which are commonplace, a semiconductor laser with a means for preventing mirror surface destruction as described above is shown in FIG.
A structure shown in FIG. 1 with a side sectional view is already known.

Section 1 (al indicates an example in which a protective film is provided on the mirror surface,
+ type 0akS substrate, 2 is nNAtGaAs clad J1
1I+, 3 is n or p 9 Ga As active layer, 4 is p
type AtGaAs cladding layer, 5 is a p-type GaAs camp, 11 is a p-side electrode, 7 is an n-side electrode, and 8 is a protective film, such as silicon dioxide (slo*), aluminum oxide (h, t, Os). A protective film 8 is formed on the mirror surface M to prevent the corrosion caused by the atmosphere mentioned above, and also to improve the effect of controlling the reflectance on the mirror surface M (usually using a thickness of 1/2 wavelength). Also (7'V
Ru.

Figure 1 (bl is the active region, mirror surface, and C1,) 5.11 where a window region is provided, and the same reference numerals as in Figure 1 (al) indicate the same target parts. For example, after eviaxially growing a non-doped (,) As i value 3', the crack layer 4 is removed from the cap layer 5 ('-)', and the depth is transferred to the spatula layer 3'. For example, a p-type active region is formed by selectively diffusing lead (Zn) in the χ grid.Also, a p-type active region is formed by selectively introducing a method such as dipping (the mirror surface N1 is an impurity θ). It is better to move it further away than 3, and the middle (JaAsJ
偕3' becomes the sind area.

In the structure shown in FIG.
Compared to As1 threat 3', the forbidden band width is 20[τn
e V ], the electron-positive-TL
The radiative recombination of y occurs in the p-type active region 3, and the y generated here is (on the other hand, the Ga
As Jiji 3' is transparent. Further, there are almost no carriers in this wind region. As a result, the light ζ
The above-mentioned mirror surface destruction is prevented.

FIG. 1 [C] is an example in which a window region is provided similarly to FIG. 1 Fbl, but as is generally done, the active layer 3
After epitaxially elongating the semiconductor layer 5y, etc., the semiconductor layer around the active region is selectively removed to activate it; The same effect as the example shown in the figure (bl) is obtained. In the figure, 3 is AtO, 05GaO, 95A, s active layer,
3' is the n-type At03G with the selected base length; 10.
7NS layer forms a window region, and 9 is a p-type Ate, 3 ()a 0.7 As @ flow blocking layer.

Although it is desirable to provide a means to prevent mirror surface destruction as described above for quantum well semiconductor lasers, the method of forming an active region by introducing impurities as described above with reference to FIG. It is also a disadvantageous method for P4 body lasers because it has a large risk of damaging the heterojunction, and cannot be applied to quantum well lasers. In addition, the embedding structure by eviaxial extensibility explained in FIG.

[dl Object of the Invention The present invention relates to a quantum well structure laser, and an object of the present invention is to provide a means for preventing mirror destruction, particularly a structure in which a window region is formed in accordance with the quantum well structure.

(e) Structure of the Invention The object of the invention is to form a well layer having a thickness equal to or less than the Doe-Broy wavelength of an electron wave, and to form a forbidden band width from the well layer. an active region in which barrier layers are laminated on each other; first and second cladding layers having a larger forbidden band width than the well layer and disposed to sandwich the active region; A semiconductor light emitting device ζ, which is provided with a window region formed by mixing mutual compositions between the semiconductors constituting at least one of the barrier layer and the cladding layer and the well layer (!:), which contact and terminate at a resonant mirror surface. This is achieved through this.

(Examples of the Invention) The present invention will now be explained in detail by way of examples with reference to the drawings.

Figures 2 [al to (C1 are the fl11 parts in the main manufacturing process of the implementation train of the present invention] [[Fig. Figuretal (D
X -X/cut tl, ii 3 (+)) is 2 and 2 (bl
) Y - Y' M 1jJi Top 0) It is a chart showing the composition ratio of aluminum ram CA-1).

Figure 2 (al) and Figure 3 (tal), n-type () a
Molecule-bearing epitaxial growth method (
The following layers are sequentially formed by the metal organic pyrolysis vapor growth method (MOCVDi'A) or the like.

The n-type GaAs buffer layer 12 has an impurity concentration equal to that of the substrate.
An example equivalent to 1 is lXl0'''Cc〃j-3]am, and the thickness is, for example, 3.5 [μm3 punch. n-type Atx'l
'ai
The thickness is, for example, approximately 1 to 1.5 [μm].

The well layer 14 is made of GaAS with a thickness of, for example, Io[nm:], and a grooved layer f fid)CGa.
The A4 composition ratio X is, for example, 0.2, and the thickness is, for example, 3 (nm) using 1-Me FAS, both of which are non-doped and formed by laminating, for example, four well layers and three barrier layers. There is. The thickness of the well layer is less than the wavelength L]-E of the Op-type AtxG, n-xAs cladding layer 15, where the At composition ratio X is, for example, 04, and the impurity concentration is, for example, 1x1017. The impurity concentration of the final p-type QaA, s cap layer 16 is, for example, lX10'9 [crn-3]. ] For example, the thickness is 03
It is set to approximately o, s (μm).

See Figure 2 (bl and Figure 3, tbl).

Mutual diffusion is caused between the well layer and the barrier layer of the quantum well structure 14 in the vicinity of a position where a resonant mirror surface is formed by diode opening or the like. At this time, mutual diffusion may also be performed with the ground layer.

An example of a method for implementing this is a method of diffusing or implanting impurity atoms or protons into the intended region.

That is, as shown in FIG.
4) Or formed from silicon dioxide (8i0.) or the like, and pass through the quantum well structure 14 with, for example, zinc (Zn), sulfur (S), etc. using a sealed tube method or the like to form an n-type Am Qal -
Either by diffusion to a depth reaching the xAs cladding layer 13, or by forming a mask 17 of, for example, gold (Au) deposited through a resist, impurity atoms or protons are implanted to the depth mentioned above by ion implantation. By the method of introducing and annealing, Atx contained in the barrier layer, Atx Ga+ -xA, and the s cladding layer 15 is diffused within the quantum well structure 14 including the well layer, the Peter junction interface disappears, and the quantum well In place of the structure 14, a nearly uniform AtxGa1-xA S region 18 is formed.

Refer to Figure 2 tc) and tdl.
) and the p-side electrode 20 made of gold/germanium (AuC).
) After providing the n-side electrode 21 by
dl-xA, perform wall-to-wall opening at the planned wall opening position in the s region 18 (this completes the single-well laser chip of the non-embodiment).

In the non-example, the light generated in the well layer of the sliver region of the quantum well structure 14 is confined in the cladding layers 13 and 15 and goes toward the resonant mirror surface M due to the opening, but the light near the resonant mirror surface M is connected to the main gate first. A- formed by mutual diffusion
tx Oa 1-
A similar effect of the window area can be obtained by subtracting 1.

The above explanation is 84ulti 0uanj, um W
el l <J'i construction was taken as an example, but Single Q
Quantum Well gQO) can also be performed in the same manner for rMA.

(gl) According to the invention as described in detail, it is possible to easily provide a window region in accordance with the quantum well structure in a quantum well semiconductor laser, thereby stabilizing the characteristics and improving reliability. This has greatly contributed to the practical application of the Kirikoido cow conductor laser, which has improved performance and excellent features and is expected to have a promising future.

[Brief explanation of the drawing]

FIG. 1 [al to (cl) are side sectional views showing an example of a conventional semiconductor laser without a quantum well structure, FIG. 2 [al to (C) are side sectional views in main manufacturing steps of an embodiment of the present invention. , FIG. 2 is a perspective view of the same example, and FIG. 3 is a chart showing the composition ratio of At on the cross section. In the figure, 11 is an n-type GaAs substrate, 12 is n
type GaAs barrier layer, 13 is n-type AtGaAs
cladding layer, 14 is Ga As well layer and At
Quantum well structure consisting of GaAs barrier layer, 15 is p-type A! GaAS ground layer, 16 is p-type GaA
s cap layer, 18 is an AtGaAs window region, 19 is a protective film, 2o is a p-side electrode, 21 is an n supply &amp;
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1iiTl (1) The scope of the patent claim described in the same specification shop, page 1, lines 5 to 14 is amended as shown in the attached sheet. (2) The same page 1, lines 19 to 14 are amended. Correct "window area" in line 20 to "area". (3) On page 7, line 17, "terminates at a resonant boundary surface" is corrected to "-disposed,". (4) Correct "1 width/domain area" on page 7, line 20 to "area". (57 Id. No. 11A, No. 15, 15th line) Injecting meat juice from the meat in this part. The present invention may be applied to a current confinement region that defines a
The region other than the current path of the listener well structure consisting of the rear layer (non-doped well layer) is used to form a current confinement region with high resistance and uniform composition by implanting inert atoms, etc. (6) 11th line of the same, 12th line, 1 window region, therefore 1- or current confinement region.” (6) Claims characterized by 1- or current confinement region” 1.-0 below the dow-plow wavelength of the electronic wave. An active region in which a well layer having a length of 1" and a barrier layer having a dust control band width corresponding to the width of the well layer are alternately laminated; first and second cladding layers, which are arranged in contact with the active region, and at least one of the barrier layer and the cladding layer and the well IeI; ,!: (11゛ ← A 144-body generating device characterized by being provided with a 411-component mixture of compositions (a region in which there is a change in the composition).

Claims (1)

[Scope of Claims] It has a layer with a wavelength below the wavelength of the wave, and an aluminum layer that is lower than the wavelength of the wave.
The layer y′ having a band width l is intersected with the layer t
11 arranged to sandwich the occupied area and the active area.
6 The first and second Krat layers mourning the Emperor's breadth, and the first and second layers of paper, which are larger than the It layer. and at least the 11th well of the previous Hj2 bar 10' layer and the 7th layer IS layer.
Layer and composition 1 = 43) One of the inheritance of semi-conducting rest 1 and also Q monthly payment name ゛: /l-package A1 and force S configuration pu (J Semiconductor Mitsugen Rishu,.