JPS58151085A - Manufacture of semiconductor laser device - Google Patents

Abstract

PURPOSE:To obtain a buried type hetero laser with good yield by a method wherein the surface of a crystal growing substrate from a liquid crystal blocking mask is projected in a filament form while performing liquid epitaxial growth. CONSTITUTION:An N-Al0.45Ga0.55As 17 and an N-GaAs 18 are laminated on the N-GaAs substrate 16, and a part of the layer 18 is removed by etching by the aq. soln of NH3+H2O2. The surface of the exposed layer 17 is an oxide film, which becomes the mask 19 for blocking liquid crystal growth, and the remaining stripe shaped N-GaAs layer becomes the substrate surface 20 for crystal growth. An N-Al0.3Ga0.7As clad 21, a non-doped GaAs active layer 22, a P-Al0.3Ga0.7As clad 23 and a P-GaAs ohmic electrode 24 are successively formed epitaxially on this substrate by a normal method. Next, the part except for the main stripe part is covered with an Si3N4 25, and metallic electrodes 26 and 27 are attached. By this constitution, crystals can be easily formed on the stripe shaped window, and accordingly the yield of the buried hetero laser is remarkably improved.

Description

[Detailed Description of the Invention] (@Akira's Techniques Part 1?) A of the semiconductor laser device according to the book Q Akihirots@Crystal Growth Method
Regarding illegality (prior art and its RI1 point) The so-called Burrisd H@t@ro Las@r (hereinafter referred to as 1-iris laser), which is embedded in a fixed active region or rad, has a low driving current, isotropic far a#
It has excellent properties such as images, and is ideal as a light source for light damage and optical information. There was a problem. In order to solve this B111 point, 111) traces a@KameH@
t@rostruatur* 工 a#er (a 下１■RazutoNecho) has been proposed. IJla to 31st show the method of expansion. In other words, first!
As shown in FIG. 1L, a liquid phase layer growth prevention mask (2) made of 81-4 is provided on the Wk plane of the eaA-single crystal substrate (1). M-44-sG&, MOOCRAD (3), unlop by normal slide boat method on this substrate.
s-Ga mu-active region (4), p-mulea Gary
By growing the crystals of 53% P-()IL MU-O(TSUKU ELECTRONICS 1K(61T)), a wafer with T cross-section *a shown in 2A is obtained.Then, the wafer is p4M and nTable 11o6 After two-electrode processing, cut out the chip Y of the semiconductor laser as shown in figure s3.In addition, in the third factor, (81.IJ in force).

Connection results, (81 and t91 are P-side and N-side electrode trays, respectively)
It is. The light emitting part of the laser is a filament-like mgm castle (4〆) obtained by the crystal hi, ★ above the striped window (called ``king stripe'') shown at -8 in Figure 1. In addition, the striped window 8' is also called a dummy region, and is provided to absorb most of the crystals precipitated from the liquid phase during liquid phase crystal growth (therefore, it is provided to suppress the long velocity wLY of the crystals). There is.

If you do not provide a dummy region, the crystal growth rate will be unstable,
It is extremely important to control the thickness of the ancient temperature range (0.1 to 0.3 μm).

However, the production yield of Ill lasers made by this method is low. This is because in the #L phase crystal member shown in the $2 diagram, crystal growth in the striped window may not occur at all, or certain axes may be missing even if the window is struck.

This is the technical problem that has caused the Eneroku laser to not be put into practical use, although it is expected to be a laser with high performance and a similar level of performance.

(Object of the invention) The object of the invention is to improve the production quality of ICH lasers.
There are 12 ways to provide IP.

(Summary of the invention 1) The main stripe state 6 is
It was inferred that the reason why the crystal growth in the second stage was difficult was that the crystal growth temperature was lower than that of the main strike prevention mask, so that the crystal growth t could not penetrate into the solution, and this was confirmed experimentally. This recommendation #i
This will be explained using a model for a solution on a substrate with a Vs groove cut out. ・In the fourth decoy, a
A substrate with a sieve of depth d is placed on top of the molten metal with a surface tension of C.
[U is in contact with the radius of curvature ρ. At this time, ρ3-(-141) is calculated from 10ω1 ρ; (♂+♂)/2
It is d.

Pressure at solution & part tP1 When the angle between the vertical plane and the straight line drawn from the center of curvature of the solution to the top of the substrate groove is 0,
Is The condition for the enemy to touch the bottom of the hook is F-2'>2#*#=+
zg, -. This condition is summarized as ρ and the above equation, and the crystallization Mjg<p, ``-±ra-.Specifically, the normal ``%'', the value of ``l'' (the solution at the time of ``# phase crystal formation''). The sum of the pressures P22XIO” dyn/dω=
1.5. am, Axllllll) 1 and 1.
, (61,±”z o, 3256 y n/a+w
And d becomes. This problem is equal to the surface tension of ordinary liquid metal.
l(l It is very small compared to dyn/m, and it can be seen that the solution does not touch the bottom of the groove.
As y n/am, Pm2XlO” dyn/a
When Lω = 1.5 μm, the groove depth (aV) for which the solution comes into contact with the groove bottom is calculated to be about d ~ 2 mm, and in reality, unless the groove depth becomes 0, the S* or III# bottom surface I understand that there is no oral contact.

In the present invention, as shown in the fifth factor, the filament-shaped crystal growth substrate surface α protrudes from the liquid phase crystal growth blocking mask 03 (141't-) by using the substrate for liquid phase crystal growth. JIm has been overcome.Since the crystal member radix plane protrudes from the crystal growth inhibition mask, it always comes into contact with the solution that inhibits crystal growth.In addition, such protruding parts are prevented from melting back due to the action of interfacial birurgy. It also has the advantage that poor crystallinity near the surface can be removed by meltback.

(Embodiment of the invention) MujX Gal-1A s/G! Lmu IH1m-
- An embodiment of the present invention in r will be described with reference to t'*6 figures to the eighth decoy. The sixth substrate is a substrate before crystal growth, which was manufactured by the following method. By continuous liquid phase crystal growth, n-G
n-mu, ea-, mu more α'ItS on amu- board shout
n-Gamuichilayera [stock] wotsuku・huffy%near+hydrogen peroxide solution? Selective etching of a part of n-GaAsPm (181) with YG solution・Exposed MutGa layer Q7
) is an oxide layer, which serves as a liquid-phase crystal growth blocking mask a field, and the striped n-Gal layer that remains unetched serves as a crystal growth substrate 1iIGllll.
becomes. In addition, the crystal growth substrate 1ilG! 1j is $3μm
, the height was 0.5 syn, and the crystal growth blocking masks am and as located on both sides were each sacrificial 10 μm.

On this substrate, a normal slide boat method was applied to form a clad Gin, una.
ops-Ga module active region ■, p- module je-MGa, ?
Muklad (c), P-G&, Roozuk electrode-IIIL+: Liquid phase crystal growth, 7th i1! A substrate having the structure shown in Jl2 is obtained. Next is the part g that becomes King Strive.
! Except for Iv, 8i, M, insulators are provided, and p4ii of the historical board! After providing an electrode layer on the I and n side surfaces th+, the semiconductor laser is cut out from the top of the semiconductor laser shown in FIG. 118.

m5IQ (=, (to), (c) are respectively p side'
Magnetic pole: 4°, n-side electrode metal.

In semiconductor laser chips that have been specially designed in this way,
No defects in crystal growth were observed at all in the striped window I:, which had become interlocked in the conventional technique.

(Effect of the invention) A BH laser, which is a type of H laser, is ideal as a light source for optical communication and optical information processing! 11! We were able to significantly improve the production yield.

(Shaped steel for the invention) The connection and material of the example is MuZ x Gal-M/Ga
Although it was rough, Gaz knee-X mu-1-yPy//
The present invention can be applied to all materials such as InP that can make a two-wheel heterojunction laser by the liquid phase crystal growth method C2. In addition, an oxide layer on the surface of 11 μLgGζ-Emu was used as an enemy phase crystal formation mask,
81. M, genus, etc. may also be used. In addition, although the active image area method of the embodiment is embedded in a straight filament shape, it does not matter if it has curved edges, loops, or branches.

[Brief explanation of the drawing]

Figures 1 to fsB are explanatory diagrams of the conventional manufacturing method of BH laser and Wk construction, and the fourth factor is St-
Diagram of model for wetting of solution on cut substrate, 5th
The figure shows a substrate equipped with a liquid-phase crystal growth inhibiting mask according to the present invention, and the sixth to SS diagrams are explanatory diagrams of the manufacturing method and structure of an ICH laser according to the present invention. ae...nGlA-substrate, fin...nmuL@,
@Ga□Muichi, 餞...nGaas, <11...
Crystal growth prevention mask, (2)...nGlA-crystal growth substrate surface, G11l-nA4-a Ga@11al cladding 1 (2)...undoped Ga moo active region,
Ci3'']>A4suG1・, Mamoukurad, (2)・
...pGaAs ohmic electrode 1k...B i, M
4. (to)...p@electrode metal, gI+
...n@electrode metal. (7317) Yoshioiri Patent Attorney Nori Yu Chikinaki (and 1 other person) Figure 1 Figure 2 Figure 4 Figure 5 Figure 6 Figure 7 ( Figure 8 7

Claims (1)

[Scope of Claims] On the semi-solid substrate using the ridge-phase crystal structure 142, there is a striped glaze 4@Crystal growth inhibition! a semiconductor crystal to form at least an active region on the substrate, and a $
By growing the two semiconductor crystals that will become the first cladding and the iJ2 cladding, the ficklement-like active region can be made to protrude beyond the two cladding layer growth prevention masks, or the crystals can be grown at the same level. 62 fathoms in solution,
A method for manufacturing a semiconductor laser device characterized by using liquid phase crystal growth.