JP2748754B2 - Semiconductor optical device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention
Integrated multiple optically coupled semiconductor optical devices.
The present invention relates to a structure of an element .

[0002]

2. Description of the Related Art FIG. 3 is a sectional view showing the structure of a conventional multi-electrode semiconductor optical device having electrodes having a heat dissipation effect.
In this figure, 1 is a common electrode also serving as a heat sink,
2, 3 are electrodes for independently injecting current, and 4 is a light emitting portion.

Next, the operation will be described. In general, the optical output and amplification characteristics of a semiconductor optical device change due to an injection current, but at the same time, the heat generated by the injection current changes the refractive index of the semiconductor and the wavelength characteristics. By applying different currents to the electrodes 2 and 3 in FIG. 3, if the semiconductor optical device in FIG. 3 is, for example, a multi-electrode DFB laser, the light output to the electrode 3 is kept constant by the current injected into the electrode 2. The oscillation wavelength can be changed by the injected current. If the semiconductor optical device shown in FIG. 3 is a multi-beam laser, the ratio of the light output of each laser beam can be changed. In FIG. 3, the common electrode 1 also serves as a heat sink for dissipating heat, and heat generated by a current flowing between the electrode 2 and the common electrode 1 and heat generated by a current flowing between the electrode 3 and the common electrode 1 are: Dissipated outside by the common electrode 1,
In this case, the heat is transmitted isotropically because the common electrode 1 of the heat sink has no anisotropy of heat conduction.

[0004]

Since the conventional multi-electrode semiconductor optical device having the common electrode 1 also serving as a heat sink is constructed as described above, for example, in FIG. And the heat generated by the current flowing through the electrode 3 easily interferes with each other. Therefore, in a semiconductor optical device whose wavelength characteristics and optical output characteristics are governed not only by the amount of injected current but also by the temperature, a plurality of electro-optical characteristics A large amount of crosstalk between the electrodes complicates the feedback method for stabilizing the light output and wavelength, or complicates the control of the light output and wavelength between each beam of the multi-beam laser. There was a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the present invention provides an anisotropic heat conduction characteristic of a common electrode serving also as a heat sink, thereby generating an electric current between a plurality of electrodes. It is an object of the present invention to obtain a semiconductor optical device with reduced heat interference.

[0006]

According to the semiconductor optical device of the present invention, the thickness of the common electrode, which also functions as a heat sink, is made thicker at the portion facing the other plurality of electrode shapes than at the portion not facing the other electrodes. Is anisotropic to the heat dissipation effect.

[0007]

According to the present invention, the common electrode serving also as a heat sink has a lower conductivity than that of the heat conduction from the thicker portion of the electrode to the thinner portion. Since the heat dissipation becomes larger, heat dissipation becomes anisotropic, and thermal interference can be reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment in which the present invention is applied to a two-electrode DFB laser. In FIG. 1, reference numeral 1 denotes a common electrode serving also as a heat sink having anisotropy in heat conduction. The common electrode 1 comprises a thick portion 1a and a thin portion 1b of the electrode. Anisotropic heat conduction is provided by forming a portion 1b at the opposite portion and a portion 1b having a small thickness at the non-opposing portion. 4 is a light emitting portion.

Most of the heat generated by the current flowing between the common electrode 1 and the electrode 2 is generated by the thin portion 1b of the electrode 1 provided on the common electrode 1, that is, the portion having a large thermal resistance. The light is emitted to the outside of the element by the common electrode 1 which also serves as a heat sink without reaching between the common electrode 1 and the electrode 3. The same can be said for the heat generated by the current flowing between the common electrode 1 and the electrode 3. As a result, the interference between the heat caused by the current between the common electrode 1 and the electrode 2 and the heat caused by the current between the common electrode 1 and the electrode 3 can be reduced. Therefore, the current flowing between the common electrode 1 and the electrode 2 has an effect on the light output and the oscillation wavelength of the light emitting portion 4, and
Since the independence between the light output of the light emitting portion 4 and the effect on the oscillation wavelength of the current flowing between the electrodes 3 and 2 is increased,
For example, it is easy to control the amount of injection current between multiple electrodes for controlling the oscillation wavelength while keeping the optical output of the oscillating light constant, or changing the optical output while keeping the oscillation wavelength constant. Become.

FIG. 2 shows the present invention applied to a two-beam array laser. In this figure, 4a and 4b are independent light emitting portions, 2 is an electrode for injecting current into the light emitting portion 4a, and 3 is an electrode for injecting current into the light emitting portion 4b. For the same reason as in the first embodiment, thermal interference between the common electrode 1 and the electrode 2 and between the common electrode 1 and the electrode 3 is reduced, so that the light flows to one light-emitting portion (for example, 4a) between adjacent beams. The effect of the heat generated by the current on the oscillation wavelength and light output of light generated in the other light emitting portion (for example, 4b) can be reduced.

Further, the present invention provides a semiconductor optical modulator array,
And optical amplifier arrays and the like, more than two electrodes possess, it
They can also be applied to a semiconductor optical functional device optically connected via one optical waveguide . In FIG. 1, if the light emitting portion 4 is replaced with an optical waveguide, the same effect as in the first embodiment can be obtained for the reason shown in the first embodiment.

Further, the present invention can be applied to a semiconductor light receiving element having three or more electrodes, such as a semiconductor light receiving element array, by replacing the light emitting part 4 in FIG. 1 with a light receiving part. It works.

[0013]

As described above, according to the present invention,
The thickness of the common electrode having a heat dissipation effect is made thicker at the portion facing the other electrode than at the portion not facing the other electrode so that the heat dissipation effect has anisotropy. A multi-electrode semiconductor optical device having small mutual crosstalk can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a two-electrode DFB laser according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a two-beam array laser according to another embodiment of the present invention.

FIG. 3 is a sectional view showing a conventional multi-electrode semiconductor optical device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Common electrode 1a Thick part 1b Thin part 2 Electrode 3 Electrode 4 Light emitting part 4a Light emitting part 4b Light emitting part

Claims (1)

(57) [Claims] 1. An optically coupled optical waveguide through one optical waveguide.
In a semiconductor optical device having a common electrode also serving as a heat sink and a plurality of independent electrodes, anisotropic heat dissipation generated by flowing a current between the common electrode and the independent electrodes is provided. A semiconductor optical device, wherein a thickness of the common electrode is greater at a portion facing each of the independent electrodes than at a portion not facing the independent electrode.