JP4629346B2 - Optical integrated device - Google Patents

Description

    The present invention relates to an optical integrated device optimal as a light source and a light receiving element in the field of optical communication.

  An optical integrated device in which an electroabsorption optical modulator (EA modulator) is coupled to a semiconductor laser element, for example, a distributed feedback semiconductor laser element (DFB laser) by a butt-joint method has attracted attention as an optical communication light source (for example, Non-patent document 1).

  FIG. 2 is a cross-sectional view along the ridge stripe showing the configuration of an example of an optical integrated device in which a DFB laser is coupled to an EA modulator. As shown in FIG. 2, an optical integrated device in which an EA modulator is coupled to a DFB laser by a butt-joining method includes a DFB laser formed on a DFB laser region 21a of a common n-InP substrate 21, and an n-InP substrate. The EA modulator is formed on 21 EA modulator regions 21b and is optically coupled to the DFB laser.

  The DFB laser has an MQW active layer structure 23 sandwiched between a n-InP lower cladding layer 22 and a separate confinement heterostructure (SCH) layer made of InGaAsP on the DFB laser region 21a of the n-InP substrate 21, InGaAsP And a laminated structure of a p-InP upper cladding layer 25 and a p-InGaAsP contact layer 26 on the diffraction grating 24. A p-electrode 27 is formed on the p-InGaAsP contact layer 26, and a common n-electrode 28 is formed on the back surface of the n-InP substrate 21. The p-InP upper cladding layer 25, the MQW active layer structure 23, and the n-InP lower cladding layer 22 constitute a pin structure.

  The EA modulator has an MQW active layer structure in which an n-InP lower clad layer 22 common to a DFB laser and both sides constituting an optical modulation layer are sandwiched by SCH layers on an EA modulator region 21b of an n-InP substrate 21. 29, and a laminated structure of a common p-InP upper clad layer 25 and a p-InGaAsP contact layer 26. The SCH-MQW active layer structure 29 has an active layer with a band gap wavelength of 1.49 μm. A p-electrode 210 is formed on the p-InGaAsP contact layer 26. The p-InP upper clad layer 25, the MQW active layer structure 29, and the n-InP lower clad layer 22 constitute a pin structure.

  The DFB laser and the EA modulator are formed into a ridge stripe (not shown) to form a waveguide. Both sides of the ridge stripe are buried with a high resistance layer (not shown) made of Fe-doped InP.

  The SCH-MQW active layer structure 23 of the DFB laser and the SCH-MQW active layer structure 29 of the EA modulator are coupled by a butt junction method. A separation groove 211 is provided between the EA modulator and the DFB laser, and the EA modulator and the DFB laser are pseudo-separated by a resistance generated by the p-InP upper cladding layer 25 portion.

`` Very High-Speed Light-Source Module up to 40 Gb / s Containing an MQW Electroabsorption Modulator integrated with DFB Laser '' IEEE J. Selected Topics in Quantum Electronics, vol.3, No.2, pp.336-343, 1997.

    Since the DFB laser is forward biased to inject current and cause laser oscillation, when the n-electrode 28 on the back surface of the n-InP substrate 21 is grounded, the laser-side p-electrode 27 applies a positive voltage. . On the other hand, the EA modulator is used with a reverse bias. When the reverse bias is small, there is almost no light absorption. However, the light absorption increases sharply as the voltage increases. It is an element that can modulate the light transmission intensity by modulating the bias. For this reason, when the n-electrode 28 on the back surface of the n-InP substrate 21 is grounded, the p-electrode 210 on the EA modulator side applies a negative voltage (reverse bias).

A separation groove 211 is provided between the EA modulator and the DFB laser, and the EA modulator and the DFB laser are pseudo-separated by a resistance generated by the p-InP upper cladding layer 25 portion. However, when the modulation operation is performed by applying a negative voltage to the p-side electrode 210 on the EA modulator side, the electric field is not only directly under the EA modulator. An electric field is also generated in the modulator layer immediately below the separation groove 211 and light absorption occurs. However, carriers generated by the light absorption must travel to the p electrode 210 on the EA modulator side over a long distance and be discharged from the electrode. Therefore, it becomes a factor of reducing the response speed.
In particular, when a large reverse bias operation state or ultra-high speed modulation is performed, this response speed deterioration factor causes a decrease in device operation speed.

  In view of the above prior art, the present invention hardly generates an electric field in the modulator layer or absorption layer immediately below the separation groove, and therefore hardly generates carriers due to light absorption. Providing an optical integrated device capable of ultra-high-speed operation, in which high-speed modulation suppresses the response speed deterioration caused by the carrier generated by this light absorption and hardly causes a significant decrease in device operation speed. The purpose is to do.

In a first invention for solving the above-described problem, a first semiconductor optical element having a pin structure and a second semiconductor optical element having a pin structure are arranged on a semiconductor substrate. The semiconductor substrate has a structure in which a lower clad layer, an active layer, and an upper clad layer are laminated. The second semiconductor optical device includes a lower clad layer, an active layer, and an upper clad layer on the semiconductor substrate. In an optical integrated device in which the active layer of the first semiconductor optical device and the active layer of the second semiconductor optical device are butt-joined,
Of the upper clad layer, the first semiconductor optical device side of the connection portion where the active layer of the first semiconductor optical device and the active layer of the second semiconductor optical device are connected is arranged on the first semiconductor optical device side. layers of the same conductivity type and the lower clad layer is inserted in contact with the active layer of the semiconductor optical device,
When operating the optical integrated device by applying a reverse bias to the pin structure of the first semiconductor optical element, applying a forward bias to the pin structure of the second semiconductor optical element, or operating as a zero bias, the lower cladding A voltage is applied only to a pn junction portion constituted by a layer of the same conductivity type as the layer and the upper cladding layer on the layer, and a voltage is applied to the active layer of the first semiconductor optical device in the connection portion It is characterized by not being applied .

According to a second invention, in the optical integrated device according to the first invention, the first semiconductor optical element is an electroabsorption optical modulator and the second semiconductor optical element is a semiconductor laser. To do.

According to a third invention, in the optical integrated device according to the first invention, the first semiconductor optical element is an electroabsorption optical modulator and the second semiconductor optical element is an optical waveguide. To do.

According to a fourth invention, in the optical integrated device according to the first invention, the first semiconductor optical element is a semiconductor light receiving element, and the second semiconductor optical element is an optical waveguide.

  Here, when the first semiconductor optical device is a semiconductor light receiving device, the active layer of the first semiconductor optical device means the light receiving layer of the semiconductor light emitting device. Further, when the second semiconductor optical device is an optical waveguide, the active layer of the second semiconductor optical device means an optical waveguide layer of the optical waveguide.

  As described above, according to the present invention, in the optical integrated device in which the active layer of the first semiconductor optical element having the pin structure is connected to the active layer of the second semiconductor optical element having the pin structure, Since a part of the upper clad layer in the portion is configured with the same conductivity type as that of the lower clad layer so that almost no externally applied voltage is applied to the active layer and becomes equipotential, the lower electrode and the upper electrode Even if a voltage is applied to the active layer, the voltage is applied only to the junction portion in the upper clad having a different conductivity type. Therefore, the applied voltage and the electric field generated by the applied layer are not applied to the active layer under the portion. Does not occur. For this reason, there is almost no generation of carriers due to light absorption, and in the case of a large reverse bias operation state or ultra-high speed modulation, the response speed deterioration factor due to the light absorption generated by the carriers is sufficiently suppressed, and in a wide voltage range. High-speed operation is possible.

    In the optical integrated device of the present invention, a first semiconductor optical element having a pin structure and a second semiconductor optical element having a pin structure are arranged on a semiconductor substrate, and an active layer of the first semiconductor optical element In an optical integrated device in which the active layer of the second semiconductor optical element is connected, a connection portion where the active layer of the first semiconductor optical element and the active layer of the second semiconductor optical element are connected A part of the upper clad layer is configured to have the same conductivity type as that of the lower clad layer, and is configured so that an applied voltage is not applied from the outside to the active layer of the connection portion. Even when a voltage is applied, the voltage is applied only to the junction part of different conductivity type in the upper clad, so that the applied voltage and the electric field caused by it are generated in the active layer under that part. do not do.

  For this reason, there is almost no generation of carriers due to light absorption, and in the case of a large reverse bias operation state or ultra-high speed modulation or light reception, the cause of response speed deterioration due to the carriers generated by this light absorption is sufficiently suppressed, and a wide voltage High speed operation is possible within the range. In addition, it is possible to operate with high light intensity, and it is possible to improve the stability and reliability of device operation even in operation with high bias and high light intensity.

  The best mode for carrying out the present invention will be described below based on examples.

  First, Embodiment 1 of the present invention will be described in detail with reference to FIG.

  As shown in FIG. 1, the DFB laser has an MQW active layer structure 13 in which an n-InP lower clad layer 12 and an SCH layer made of InGaAsP are sandwiched between a DFB laser region 11a of an n-InP substrate 11 and an InGaAsP. And a laminated structure of a p-InP upper cladding layer 15 on the diffraction grating 14 and a p-InGaAsP contact layer 16. A p-electrode 17 is formed on the p-InGaAsP contact layer 16, and a common n-electrode 18 is formed on the back surface of the n-InP substrate 11.

  The EA modulator has an MQW active layer structure in which an n-InP lower clad layer 12 common to a DFB laser and both sides constituting an optical modulation layer are sandwiched between SCH layers on an EA modulator region 11b of an n-InP substrate 11. 19, a MQW active layer structure (light modulation layer) 19 and a p-InP upper cladding layer 15 common to the DFB laser and a p-InGaAsP contact layer 16 stacked structure. The MQW active layer structure 19 has an active layer having a band gap wavelength of 1.49 μm. A p-electrode 110 is formed on the p-InGaAsP contact layer 16.

  The DFB laser and the EA modulator are formed into a ridge stripe (not shown) to form a waveguide. Both sides of the ridge stripe are embedded with a high resistance layer (not shown) made of polyimide.

  The MQW active layer structure 13 of the DFB laser and the MQW active layer structure 19 of the EA modulator are coupled by a butt joint method. A separation groove 111 is provided between the EA modulator and the DFB laser, and the EA modulator and the DFB laser are pseudo-separated by a resistance generated by the p-InP upper cladding layer 15 portion.

  In the DFB laser, the n-electrode 18 on the back surface of the n-InP substrate 11 is grounded, and a positive voltage is applied to the p-electrode 17 on the laser side so as to inject current forward and cause laser oscillation.

  On the other hand, the EA modulator is used with a reverse bias. When the reverse bias is small, there is almost no light absorption. However, the light absorption increases sharply as the voltage increases. By modulating the bias, the light transmission intensity can be modulated. For this reason, the n electrode 18 on the back surface of the n-InP substrate 11 is grounded, and a negative voltage (reverse bias) is applied to the p electrode 110 on the EA modulator side.

  A separation groove 111 is provided between the EA modulator and the DFB laser, and the EA modulator and the DFB laser are pseudo-separated by a resistance generated by the p-InP upper cladding layer 15 portion. Since the electric field is not completely separated, when a negative voltage is applied to the p-electrode 110 on the EA modulator side and the modulation operation is performed, the electric field is not limited to the portion immediately below the EA modulator, It is also applied to the lower part of the separation groove 111.

  However, in this embodiment, the n-InP layer 112 is provided as a part of the upper clad layer on the MQW active layer structure 19 constituting the light modulation layer only in the portion directly under the separation groove 111, and this n-InP layer Since a voltage is applied only to the pn junction portion composed of the upper cladding layer 15 and the p-InP upper cladding layer 15 thereabove, a light modulation layer (existing under the n-InP layer 112) (MQW active) located therebelow No voltage is applied to the portion of (layer structure) 19, and therefore no electric field is generated by the applied voltage, so that no additional light absorption occurs even if the reverse bias is greatly changed.

For this reason, the reverse bias increases as seen in the conventional device, and no photocarrier is generated immediately below the separation groove. Therefore, response speed deterioration due to optical carrier accumulation and carrier travel speed control due to this component is observed. Good response characteristics were obtained up to the high bias region.
In this embodiment, both sides of the ridge stripe are embedded with polyimide, but may be embedded with a semiconductor high resistance layer made of semi-insulating InP doped with Fe, Ru, or the like.

  In this embodiment, n-InP is used as a substrate. However, a semi-insulating InP substrate is used, an n-InP or n-InGaAsP contact layer is provided thereon, and an n-electrode is similarly formed thereon. It goes without saying that similar characteristics can be obtained even in the form.

  In this embodiment, n-InP is used as the substrate. However, p-InP may be used to replace p and n in the above-described embodiment. Further, a semi-insulating InP substrate is used, and a p-InP or p-InGaAsP contact layer is provided on the semi-insulating InP substrate, and a p-electrode is similarly formed thereon. Needless to say, similar characteristics can be obtained.

  In addition, this embodiment is an example using an InGaAsP material system, but other material systems such as an InGaAlAs system, an AlGaAs system, an InGaNAs system, and an InGaAsSb system can be similarly applied.

  The above example relates to the integration of a semiconductor laser and an optical modulator, but since the semiconductor laser and the semiconductor optical amplifier are similarly used with forward bias, even if the semiconductor laser part is replaced with a semiconductor optical amplifier, The same applies.

  Next, a second embodiment of the present invention will be described in detail with reference to FIG.

  The optical waveguide includes an n-InP lower clad layer 32, an optical waveguide layer 33, a p-InP upper clad layer 35, and a p-InGaAsP contact layer common to the EA modulator on the optical waveguide region 31a of the n-InP substrate 31. It consists of 36 laminated structures. A p-electrode 37 is formed on the p-InGaAsP contact layer 36, and a common n-electrode 38 is formed on the back surface of the n-InP substrate 31.

  The EA modulator has an MQW active layer structure in which an n-InP lower clad layer 32 common to an optical waveguide is sandwiched between SCH layers on an EA modulator region 31b of an n-InP substrate 31, and both sides constituting the optical modulation layer are sandwiched between SCH layers. 39, a stacked structure of a p-InP upper cladding layer 35 and a p-InGaAsP contact layer 36 on an MQW active layer structure (light modulation layer) 39. The SCH-MQW active layer structure 39 has an active layer with a band gap wavelength of 1.49 μm. A p-electrode 310 is formed on the p-InGaAsP contact layer 36.

  The optical waveguide and the EA modulator are formed into a ridge stripe (not shown), and waveguides are formed on both sides of the EA modulator. Both sides of the ridge stripe are embedded with a high resistance layer (not shown) made of polyimide.

  The optical waveguide layer 33 and the SCH-MQW active layer structure 39 of the EA modulator are coupled by a common layer structure. A separation groove 311 is provided between the EA modulator and the optical waveguide, and the EA modulator and the optical waveguide are pseudo-separated by a resistance generated by the p-InP upper cladding layer 35 portion.

  In the optical waveguide, the n-electrode 38 on the back surface of the n-InP substrate 31 is grounded, and the p-electrode 37 on the optical waveguide side is also grounded so that the optical waveguide is zero-biased and hardly absorbs light.

  On the other hand, the EA modulator is used with a reverse bias. When the reverse bias is small, there is almost no light absorption. However, the light absorption increases sharply as the voltage increases. By modulating the bias, the light transmission intensity can be modulated. For this reason, the n-electrode 38 on the back surface of the n-InP substrate 31 is grounded, and a negative voltage (reverse bias) is applied to the p-electrode 310 on the EA modulator side.

  A separation groove 311 is provided between the EA modulator and the optical waveguide, and the EA modulator and the optical waveguide are pseudo-separated by a resistance generated by the p-InP upper cladding layer 35 portion. , When the modulation operation is performed by applying a negative voltage to the p-electrode 310 on the EA modulator side, the electric field is not only directly under the EA modulator, The voltage is also applied to a portion below the separation groove 311.

  However, in this embodiment, the n-InP layer 312 is provided as a part of the upper clad layer on the MQW active layer structure 39 constituting the light modulation layer only in the portion directly under the separation groove 311, and this n-InP layer Since a voltage is applied only to the pn junction portion composed of 312 and the p-InP upper cladding layer 35 thereon, the SCH-MQW active layer structure (under the n-InP layer 312) located therebelow Since no voltage is applied to the (light modulation layer) 39 portion, and therefore no electric field is generated by the applied voltage, additional light absorption does not occur even if the reverse bias is greatly changed.

  For this reason, the reverse bias increases as seen in the conventional device, and no photocarrier is generated immediately below the separation groove. Therefore, response speed deterioration due to optical carrier accumulation and carrier travel speed control due to this component is observed. Good response characteristics were obtained up to the high bias region.

In this embodiment, the optical waveguide layer 33 and the SCH-MQW active layer structure 39 of the EA modulator are coupled by a common layer structure. Needless to say, it may be composed of an MQW semiconductor layer having a non-absorbing composition or a bulk semiconductor layer having a uniform composition.
In this embodiment, both sides of the ridge stripe are embedded with polyimide, but may be embedded with a semiconductor high resistance layer made of semi-insulating InP doped with Fe, Ru, or the like.

  In this embodiment, n-InP is used as a substrate. However, a semi-insulating InP substrate is used, an n-InP or n-InGaAsP contact layer is provided thereon, and an n-electrode is similarly formed thereon. It goes without saying that similar characteristics can be obtained even in the form.

  In this embodiment, n-InP is used as the substrate. However, p-InP may be used to replace p and n in the above-described embodiment. Further, a semi-insulating InP substrate is used, and a p-InP or p-InGaAsP contact layer is provided on the semi-insulating InP substrate, and a p-electrode is similarly formed thereon. Needless to say, similar characteristics can be obtained.

  In addition, this embodiment is an example using an InGaAsP material system, but other material systems such as an InGaAlAs system, an AlGaAs system, an InGaNAs system, and an InGaAsSb system can be similarly applied.

  Next, a third embodiment of the present invention will be described in detail with reference to FIG.

  The optical waveguide is formed on the optical waveguide region 41a of the n-InP substrate 41. The n-InP lower cladding layer 42, the optical waveguide layer 43, the p-InP upper cladding layer 45, and the p-InGaAsP contact layer which are common to the optical receiver. It consists of 46 laminated structures. The optical waveguide layer 43 is made of a semiconductor having a band gap wavelength of 1.25 μm. A p-electrode 47 is formed on the p-InGaAsP contact layer 46, and a common n-electrode 48 is formed on the back surface of the n-InP substrate 41.

  The optical receiver includes an n-InP lower clad layer 42 common to the optical waveguide, an MQW active layer structure (light receiving layer) 49, and a p on the light receiving layer 49 on the light receiver region 41b of the n-InP substrate 41. It has a laminated structure of an -InP upper cladding layer 45 and a p-InGaAsP contact layer 46. The light receiving layer 49 is made of InGaAs with both sides sandwiched by InGaAsP. A p-electrode 410 is formed on the p-InGaAsP contact layer 46.

  The optical waveguide and the optical receiver are formed into a ridge stripe (not shown), and waveguides are formed on both sides of the optical receiver. Both sides of the ridge stripe are embedded with a high resistance layer (not shown) made of polyimide.

  A separation groove 411 is provided between the optical receiver and the optical waveguide, and the optical receiver and the optical waveguide are pseudo-separated by a resistance generated by the p-InP upper clad layer 45 portion.

  The optical waveguide is in a zero bias state by grounding the n-electrode 48 on the back surface of the n-InP substrate 41 and grounding the p-electrode 47 on the optical waveguide side.

  On the other hand, the optical receiver is used by being reverse-biased, and when sufficient reverse bias is applied, light absorption is saturated and stable light reception becomes possible. For this reason, the n-electrode 48 on the back surface of the n-InP substrate 41 is grounded, and a negative voltage (reverse bias) is applied to the p-electrode 410 on the optical receiver side.

  A separation groove 411 is provided between the optical receiver and the optical waveguide, and the optical receiver and the optical waveguide are pseudo-separated by a resistance generated by the p-InP upper cladding layer 45 portion. In this case, when the light receiving operation is performed by applying a negative voltage to the p-electrode 410 on the optical receiver side, the electric field is not only directly under the optical receiver, The voltage is also applied to the lower part of the separation groove 411.

  However, in this embodiment, the n-InP layer 412 is provided as a part of the upper clad layer on the light receiving layer structure 49 only in the portion immediately below the separation groove 411. Since a voltage is applied only to the pn junction portion composed of the -InP upper clad layer 45, the voltage is applied to the portion of the modulator layer 49 located under the n-InP layer 412 (below the n-InP layer 412). Therefore, since an electric field due to an applied voltage is not generated, additional light absorption does not occur even if the reverse bias is changed greatly.

  For this reason, the reverse bias increases as seen in the conventional device, and no photocarrier is generated immediately below the separation groove. Therefore, response speed deterioration due to optical carrier accumulation and carrier travel speed control due to this component is observed. Good response characteristics were obtained up to the high bias region.

In this embodiment, the optical waveguide layer structure 43 and the light receiving layer structure 49 of the optical receiver are coupled by different layer structures, but the optical waveguide layer structure 43 has no composition for absorbing transmitted light at all. Needless to say, the MQW semiconductor layer, a bulk semiconductor layer having a uniform composition, or the same layer as the light receiving layer may be used.
In this embodiment, both sides of the ridge stripe are embedded with polyimide, but may be embedded with a semiconductor high resistance layer made of semi-insulating InP doped with Fe, Ru, or the like.

  In this embodiment, n-InP is used as a substrate. However, a semi-insulating InP substrate is used, an n-InP or n-InGaAsP contact layer is provided thereon, and an n-electrode is similarly formed thereon. It goes without saying that similar characteristics can be obtained even in the form.

  In this embodiment, n-InP is used as the substrate. However, p-InP may be used to replace p and n in the above-described embodiment. Further, a semi-insulating InP substrate is used, and a p-InP or p-InGaAsP contact layer is provided on the semi-insulating InP substrate, and a p-electrode is similarly formed thereon. Needless to say, similar characteristics can be obtained.

  In addition, this embodiment is an example using an InGaAsP material system, but other material systems such as an InGaAlAs system, an AlGaAs system, an InGaNAs system, and an InGaAsSb system can be similarly applied.

  In the first, second, and third embodiments, only a structure in which two sets of devices, ie, a semiconductor laser and an optical modulator, and an optical modulator, a photoreceiver, and an optical waveguide are integrated, is shown. Even a structure in which a plurality of semiconductor lasers, light modulators, light receivers, semiconductor optical amplifiers, etc. are integrated in a long optical waveguide, the same configuration can be applied between them. Needless to say.

  The present invention forms a reverse-biased semiconductor optical element (for example, EA modulation or light receiving element) and a forward (or zero) biased semiconductor optical element (for example, a semiconductor laser or an optical waveguide) on the same substrate. This can be applied to an optical integrated device in which the active layers are butt-joined, and a high device operation speed can be ensured even if a large reverse bias operation or ultrahigh-speed modulation is performed.

1 is a schematic structural diagram of an optical integrated device according to Embodiment 1 of the present invention. Schematic structure diagram of a conventional optical integrated device. FIG. 6 is a schematic structural diagram of an optical integrated device according to Embodiment 2 of the present invention. FIG. 5 is a schematic structural diagram of an optical integrated device according to Embodiment 3 of the present invention.

Explanation of symbols

11, 21, 31, 41 n-InP substrate 12, 22, 32, 42 n-InP lower clad layer 13, 23 MQW active layer structure 33, 43 Optical waveguide layer 14, 24 Diffraction grating 15, 25, 35, 45 p -InP upper clad layer 16, 26, 36, 46 Contact layer 17, 27, 37, 47 p-electrode 18, 28, 38, 48 n-electrode 19, 29, 39 MQW active layer structure 49 Light-receiving layer 110, 210, 310 , 410 p electrode 1111, 211, 311, 411 separation groove 112, 212, 312, 412 n-InP layer

Claims (4)

A first semiconductor optical element having a pin structure and a second semiconductor optical element having a pin structure are disposed on a semiconductor substrate, and the first semiconductor optical element has a lower cladding layer and an active layer on the semiconductor substrate. The second optical semiconductor device has a structure in which a lower clad layer, an active layer, and an upper clad layer are laminated on the semiconductor substrate. In addition, in the optical integrated device in which the active layer of the first semiconductor optical element and the active layer of the second semiconductor optical element are butt-joined,
Of the upper clad layer, the first semiconductor optical device side of the connection portion where the active layer of the first semiconductor optical device and the active layer of the second semiconductor optical device are connected is arranged on the first semiconductor optical device side. layers of the same conductivity type and the lower clad layer is inserted in contact with the active layer of the semiconductor optical device,
When operating the optical integrated device by applying a reverse bias to the pin structure of the first semiconductor optical element, applying a forward bias to the pin structure of the second semiconductor optical element, or operating as a zero bias, the lower cladding A voltage is applied only to a pn junction portion constituted by a layer of the same conductivity type as the layer and the upper cladding layer on the layer, and a voltage is applied to the active layer of the first semiconductor optical device in the connection portion An optical integrated device configured to prevent the light from being applied . The optical integrated device according to claim 1 .
An optical integrated device, wherein the first semiconductor optical element is an electroabsorption optical modulator and the second semiconductor optical element is a semiconductor laser. The optical integrated device according to claim 1 .
An optical integrated device, wherein the first semiconductor optical element is an electroabsorption optical modulator and the second semiconductor optical element is an optical waveguide. The optical integrated device according to claim 1 .
An optical integrated device, wherein the first semiconductor optical device is a semiconductor light receiving device, and the second semiconductor optical device is an optical waveguide.

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