JPS59210681A - Manufacture of semiconductor laser - Google Patents

Abstract

PURPOSE:To form the end surface of a resonator smoothly and vertically without being strained and damaged by forming the resonator on a substrate of a 001 surface in the 100 direction and forming the end surface of the resonator to a 100 surface by using a chemical etching liquid. CONSTITUTION:A laser wafer 4 is prepared by forming a growth layer 3 on an InP substrate 1 of a 001 face so that an active region 2 consisting of GaInAsP, a laser resonator, is directed in the 100 direction. An electrode 5 is shaped on the wafer 4, and striped etching masks 6 using cavity length as width are formed on the electrode 5 in the 010 direction. The electrode 5 is etched while using the masks 6 as masks, and the wafer 4 is etched up to the lower section of the region 2 by an etchent having large surface orientation dependency. Consequently, an etching end surface forms verticality, a 100 face, and a Fabry- Perot specular surface is constituted. According to the method, the end surface of the resonator can be formed vertically through chemical etching, and the end surface of the resonator is not strained and damaged.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method of manufacturing a semiconductor laser.

(Prior art) Conventional semiconductor lasers have formed a resonator in the <110> or <i i O> direction on a (, o o i ) substrate, and formed an end face between the folds or by etching. .

However, among these methods, the method using interfolds has the disadvantage that it is easily distorted or damaged by the blade. In addition, when etching is used, there is a disadvantage that the end face has an inverted mesa or forward mesa shape due to surface orientation dependence, and the loss is large for a shifted vertical resonator.Furthermore, dry etching such as reactive ion etching has the disadvantage that chemical etching Etching has the disadvantage that smooth end surfaces cannot be obtained and loss is large.

(Objective of the Invention) The present invention has been made in view of the above points, and an object thereof is to provide a method for manufacturing a semiconductor laser that can form a resonator end face smoothly and vertically without causing distortion or scratches. .

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2, taking an InGaAsP/InP semiconductor laser as an example.

In FIG. 1(a), reference numeral 1 is an InP (001) substrate. First, a grown layer 3 made of sGaInAsP is grown on the substrate 1 so that the active region 2, that is, the laser cavity, is in the <100> direction. A laser wafer 4 is created by forming a laser wafer 4 using a conventional method. Here, the laser wafer 4
The bare hand may be either a gain waveguide type or a refractive index waveguide type.

Next, an electrode 5 is formed on the radar wafer 4, and a striped etching mask 6 whose width is the resonator length is formed on the electrode 5 by photowork.
(FIG. 1(b)).

Thereafter, the electrode 5 is etched using the etching mask 6 as a mask, and the laser wafer 4 is further etched down to the bottom of the active region 2 using an etchant having a strong surface orientation dependence such as bromine-methanol (FIG. 1(C)). Then, the etched end face (a part of which becomes the resonator end face) becomes a vertical, ie (ioo) plane, and a seven-sided bellows mirror surface is formed.

After the above, the mask 6 is removed as shown in FIG. 1(d). Then, the laser wafer 4 with the electrode 5 is attached to the thin line 7. shown in FIG. 1(d). ．． <110> as shown in 72
and -J to a predetermined magnitude in the <-11o> direction! #Open and cut out the laser chip. This cut out fcl chip is shown in FIG.

(Effects of the Invention) As is clear from the above embodiment, in the method for manufacturing a semiconductor laser of the present invention, a semiconductor laser resonator is formed in the <ioo> direction on a (001) plane substrate, and A resonator end face is formed in the (ioo) plane, that is, perpendicularly, using a chemical etching solution with strong orientation dependence. Therefore, according to the method of the present invention, it is possible to form the resonator end face perpendicularly by chemical etching without having to pass between the bones. Furthermore, since the method uses chemical etching, no strain or damage is caused to the resonator end face. The resulting semiconductor laser has a smooth edge surface.
Coupled with the fact that the end surface is vertical, there is little loss, and the efficiency can be maintained at the same level as in the case of using an interosseous method.

In addition, in one embodiment, the tip is cut out by the interbone in the final step, but since the end face of the vibrator has already been vertically formed by chemical etching before that, this valve opening step is not necessary. It can be carried out with high yield and in a simple manner.

(Other Examples) Although the case of manufacturing a laser chip has been described in one embodiment, the present invention can also be applied to the case of integrating elements on a semi-insulating substrate.

[Brief explanation of the drawing]

FIGS. 1 and 2 are perspective views for explaining an embodiment of the method for manufacturing a semiconductor laser according to the present invention. 1... InP (001) substrate, 2... Active region, 4
... Laser wafer, 6... Etching mask. Patent applicant Oki Electric Industry Co., Ltd.

Claims (1)

[Claims] A semiconductor laser resonator is mounted on a (001) plane substrate with <10
0> direction, and a resonator end face is formed in the (100) plane using a chemical etching solution that is strongly dependent on the plane orientation.