JPS59193083A - Semiconductor laser device for fiber loading - Google Patents

Abstract

PURPOSE:To enable to easily realize the good coupling of the light emitting part with the fiber loading part by a method wherein a part of a stripe recess groove provided on a substrate is used as the guide for an optical fiber. CONSTITUTION:On the N type substrate 1, an N type guide layer 2 having a forbidden band width larger than that of the substrate 1, an N type or P type active layer 3 having a forbidden band width smaller than that of the layer 2 and larger than that of the substrate 1, a P type optical guide layer 4 having the same forbidden band width as that of the layer 2, and an N type cap layer made of the same material as that of the layer 3 are successively formed. Next, a P<+> diffused layer 6 having a fixed width and a depth reaching a part of the layer 4 in accordance with said groove of the substrate 1 is formed. Then, after selective etching to the layer 2 by using a protection film rectangularly intersecting with said groove of the substrate 1 and having a fixed length, an insulation protection film is formed at the etched part. Electrodes 7 and 8 are provided on the front surface of the layer 5 and the back surface of the substrate 1. Thereby, the position of the light emitting part and the center of the optical fiber can be provided on the same optical axis.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to the alignment of a semiconductor laser device and an optical fiber, and in particular to a fiber attachment device that can easily achieve good coupling between a semiconductor laser device and an optical fiber. A light source related to semiconductor laser devices and generally used in optical fiber communication devices.

consists of a semiconductor laser device, a metal or semiconductor submount, and a metal heat sink. The light emitting part of this semiconductor laser device is extremely small, measuring approximately 5 μm x 1 μm, and the intensity of its output light has a glass distribution, making it extremely difficult to align it with a fiber that has a particularly small core diameter, making it difficult to monitor. However, there was a lack of productivity as it required assembly.

Conventionally, in order to solve the above-mentioned problem, a V-groove or a concave groove for positioning the optical fiber was formed on the mount to simplify the positioning of the semiconductor laser device and the optical fiber.

However, even if this conventional technology is used, highly accurate alignment between the V-groove or concave groove formed on the submount and the semiconductor laser device is required, and in particular, the connection between the semiconductor laser device and the submount requires solder ( In, Au8n)
Because of this, it was difficult to control the thickness of the spear uniformly2, and it was impossible to ensure high positional accuracy (±05 μm culm degree). Furthermore, even if you connect while checking the alignment with the fiber using a monitor light, there is a risk that the solder will move once it hardens, and there is a possibility that the position will change due to solder deterioration over time. It had some drawbacks.

[Purpose of the invention]

An object of the present invention is to eliminate the drawbacks of the prior art and to provide a semiconductor laser device having a structure in which a light emitting section and a fiber mounting section of the semiconductor laser device are integrated, thereby easily achieving good coupling. be.

[Summary of the invention]

A 0-type semiconductor light guide layer having a striped groove of a predetermined width; a p-type or p-type semiconductor active layer having a larger bandgap than the semiconductor substrate; a p-type semiconductor optical kite layer having the same bandgap as the moon-shaped semiconductor optical guide layer; and the 0-type or p-type semiconductor active layer. After successively forming an n-type semiconductor camp layer made of the same material as , the n-type semiconductor camp layer has a predetermined width, corresponds to the striped groove of the n-type semiconductor substrate, and has a layer of the p-type semiconductor optical guide layer. A p+ diffusion layer having a depth reaching a part of the substrate is provided, and a protective film having a predetermined length and perpendicular to the groove on the n-type semiconductor substrate is provided to selectively cover up to the first layer of the n-type semiconductor light guide. After engraving,
An insulating protective film is formed on the etched portion, including the p+ diffusion layer, the surface of the n-type semiconductor camp layer, and the n-type semiconductor camp layer.
This is a semiconductor laser device for attaching a fiber, characterized in that electrodes are provided on the back surface of a shaped semiconductor substrate.

[Embodiments of the invention]

Hereinafter, one embodiment will be described using the drawings, taking the case of GaAs as an example.

In FIG. 1, an n-type GaAlAs optical guide having a wider forbidden band width than the gap-shaped GaAs substrate is placed on an n-type GaAs substrate 1 having striped grooves of a predetermined width.
"N2 and the 0 type G a AI A s light guide layer 2
0-type or p-type GaAlAs which is smaller and has a larger forbidden band width than the 0-type GaAs substrate 1;
an active layer 3; a p-type light guide layer 4 having the same forbidden band width as the n-type light guide layer 2; and the p-type or p-type GaA layer.
After sequentially and continuously forming an n-type GaAlAs cap layer made of the same material as the lAs active layer 5 using a normal epitaxial growth method, a stripe of the n-type GaAlAs substrate 1 having a predetermined width (5 to 10 μm) is formed. A p+ diffusion layer 6 having a depth that reaches a part of the p-type GaAlAs optical guide layer 4 is formed by diffusing Zu using a normal thermal diffusion method, corresponding to the shaped groove.

Next, as shown in FIG.
Using an etching solution (for example, a photoresist film) that selectively etches the GaAs layer containing Al up to the n-type GaA, lAs layer 2, using a protective film (for example, a photoresist film) having a
For example, HP: H2O2: H20=2:1:20
), an insulating protective film (for example, a Sin film) is formed on the etched portion, and the photoresist film is removed. Shape G
An Au-based electrode 7 and an electrode 8 are provided on the surface of the aAlAs cap layer 50 and the back surface of the mouth-shaped GaAs substrate 1, respectively.

Next, a case will be described in which an optical fiber is attached to the semiconductor laser device having the above structure. The width of the striped groove on the p-type GaAs substrate 1 is 4 to 8 μm, the core diameter of the optical fiber is 2 μm, and the clad diameter of the optical fiber is 5 to 10 μm (
In the case of the most common single fiber), the n-type Ga
If the thickness of the AIA, s optical guide layer 2 is set to about 15 to 3 μIn, the n-type or p-type GaAIAs layer 3
The center light emitting part of the optical fiber and the center of the core of the optical fiber can be placed on the same optical axis.

〔Effect of the invention〕

Conventionally, it was difficult to align the semiconductor laser device and the optical fiber, and the position of the pole 5 semiconductor laser device sometimes changed due to solder deterioration over time, but in the present invention, the substrate of the semiconductor laser device By using a part of the striped groove provided above as a guide for the optical fiber, the light emitting part position and the center of the optical fiber can be provided on the same optical axis. As a result, high binding efficiency can be obtained very easily, and since there is no part that fluctuates over time, stable binding efficiency can be maintained.

[Brief explanation of drawings]

FIGS. 1 and 2 are explanatory views of the manufacturing process of a semiconductor laser device for attaching a fiber according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... N-type semiconductor substrate, 2... 0-type semiconductor optical guide layer, 3... N-type or p-type semiconductor active layer, 4...
- P-type semiconductor light guide layer, 5... N-type semiconductor cap layer, 6... Anti-diffusion layer, 7... Au-based electrode, 8...
・Au-based electrode. Figure 1

Claims (1)

[Claims] 1 An n-type semiconductor substrate having striped grooves of a predetermined width is provided with an n-type semiconductor substrate having a forbidden band width larger than that of the n-type semiconductor substrate.
an n-type semiconductor light guide layer, an n-type or p-type semiconductor active layer having a bandgap smaller than the n-type semiconductor light guide layer and larger than the n-type semiconductor substrate, and the in-type semiconductor light guide layer; After sequentially and continuously forming a mouth-shaped semiconductor light guide layer having the same forbidden band width and an n-type semiconductor cap layer made of the same material as the n-type or p-type semiconductor active layer, A p+ diffusion layer is provided that corresponds to the striped grooves of the 0-type semiconductor substrate and has a depth that reaches a part of the opening-shaped semiconductor light guide layer, and is perpendicular to the grooves on the n-type semiconductor substrate, and The reason for selectively etching up to the mouth-shaped semiconductor light guide layer using a protective film of a predetermined length is to form an insulating protective film on the etched portion, including the da diffusion layer, the n-type cap layer surface and the n-type cap layer surface;
Semiconductor laser device 0 for fiber attachment, characterized in that electrodes are provided on the back side of a shaped semiconductor substrate.