Optical Semiconductor Module

Abstract

To provide an optical semiconductor module capable of achieving a wide band.SOLUTION: An optical semiconductor module 1 according to one embodiment comprises: an AlN substrate 8 that has a transmission line 11 and on which a semiconductor laser element 10 is placed; a block 9 formed of a low-dielectric constant material and on which an inductor 15 is placed; and a housing that accommodates the AlN substrate 8 and the block 9. The inductor 15 is connected with the transmission line 11 via a wire W9. The semiconductor laser element 10 is connected with the transmission line 11 via a wire W7. An inductance of the wire W9 is larger than that of the wire W7.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to an optical semiconductor module. [Background technology]

[0002] Patent Document 1 describes a semiconductor module having a laser section and an optical modulator section fabricated on a substrate. The semiconductor module includes a semiconductor laser in which a DFB laser and an EA modulator are integrated, and a subcarrier having high-frequency wiring that is a coplanar wiring. The semiconductor laser has a ground electrode on the back surface. A step consisting of an upper stage and a lower stage is formed on the upper surface of the subcarrier, and the lower surface of the subcarrier is flat. The high-frequency wiring has a coplanar line formed on the upper stage of the upper surface of the subcarrier. The coplanar line includes a ground wiring and a signal wiring. A ground electrode is formed on the lower stage of the upper surface of the subcarrier. The semiconductor laser is arranged so that the ground electrode provided on the back surface contacts the ground electrode of the subcarrier. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-107920 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, optical semiconductor modules may have a bias tee (bias T) that supplies a bias to a semiconductor laser or a driver IC that drives the semiconductor laser. In the bias T, a method of connecting a wire to a high-frequency line is adopted. In this case, however, a dip (transmission dip) in the frequency characteristics (transmission characteristics) caused by the inductance and parasitic capacitance of the wire can become a problem. For example, if a high-frequency signal propagating through a high-frequency line is degraded by a transmission dip, the waveform quality of an optical transmission signal output from an optical semiconductor module is degraded. Therefore, in order to obtain good waveform quality in an optical transmission signal, it is required to realize a wide bandwidth of the transmission dip so that the high-frequency signal is not degraded even when a bias T is present.

[0005] An object of the present disclosure is to provide an optical semiconductor module that can realize a broadband. [Means for solving the problem]

[0006] An optical semiconductor module according to one aspect of the disclosure includes a substrate having a transmission line and on which a semiconductor laser element is mounted, a block formed of a low dielectric constant material and on which an inductor is mounted, and a housing that houses the substrate and the block, wherein the inductor is connected to the transmission line via a first wire, and the semiconductor laser element is connected to the transmission line via a second wire, and the inductance of the first wire is greater than the inductance of the second wire.

[0007] An optical semiconductor module according to another aspect of the present disclosure includes a substrate on which a semiconductor laser element is mounted, a block made of a low dielectric constant material and having a transmission line and on which an inductor is mounted, and a housing that houses the substrate and the block, wherein the inductor is connected to the transmission line via a first wire, and the semiconductor laser element is connected to the transmission line via a second wire, and the inductance of the first wire is greater than the inductance of the second wire. Effect of the Invention

[0008] According to the present disclosure, a broadband can be realized. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a plan view illustrating a schematic internal structure of an optical semiconductor module according to an embodiment. [Diagram 2] FIG. 2 is a plan view showing a schematic diagram of a substrate on which a semiconductor laser element is mounted and a block on which an inductor is mounted in an optical semiconductor module. [Diagram 3] FIG. 3 is a side view that illustrates a schematic diagram of an inductor mounted on a block. [Figure 4] FIG. 4 is a plan view showing a schematic diagram of a substrate on which a semiconductor laser element is mounted and a block on which an inductor is mounted in an optical semiconductor module different from that in FIG. [Diagram 5] FIG. 5 is a diagram showing an equivalent circuit of an exemplary optical semiconductor module. [Figure 6] FIG. 6 is a diagram showing an equivalent circuit obtained by simplifying the equivalent circuit of FIG. [Figure 7] FIG. 7 is a diagram showing an equivalent circuit of the optical semiconductor module according to the reference example. [Figure 8] FIG. 8 is a graph showing an example of the relationship between frequency and transmission characteristics. [Figure 9] FIG. 9 is a graph showing an example of the relationship between frequency and transmission characteristics. [Figure 10] FIG. 10 is a diagram showing an equivalent circuit of an optical semiconductor module according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [Description of the embodiment of the present invention] First, the contents of the embodiments of the present disclosure will be listed and described. An optical semiconductor module according to an embodiment of the present disclosure includes a substrate having a transmission line and on which a semiconductor laser element is mounted, a block formed of a low dielectric constant material and on which an inductor is mounted, and a housing that houses the substrate and the block, the inductor is connected to the transmission line via a first wire, the semiconductor laser element is connected to the transmission line via a second wire, and the inductance of the first wire is larger than the inductance of the second wire.

[0011] In this optical semiconductor module, the substrate has a transmission line, and an inductor is placed on the block. The semiconductor laser element is mounted on the substrate. The block is made of a low dielectric constant material. Therefore, parasitic capacitance can be reduced. Also, the inductance of the first wire connecting the inductor and the transmission line is larger than the inductance of the second wire connecting the semiconductor laser element and the transmission line. Since the inductance of the first wire connecting the inductor and the transmission line is large, a wide bandwidth can be achieved even in the presence of a bias T.

[0012] An optical semiconductor module according to another embodiment of the present disclosure includes a substrate on which a semiconductor laser element is mounted, a block made of a low dielectric constant material and having a transmission line and on which an inductor is mounted, and a housing that accommodates the substrate and the block, wherein the inductor is connected to the transmission line via a first wire, and the semiconductor laser element is connected to the transmission line via a second wire, and the inductance of the first wire is greater than the inductance of the second wire.

[0013] In this optical semiconductor module, a block has a transmission line, and an inductor is mounted on this block. A semiconductor laser element is mounted on a substrate. As in the optical semiconductor module described above, the block is made of a low dielectric constant material, so that parasitic capacitance can be reduced. In addition, the inductance of the first wire connecting the inductor and the transmission line is greater than the inductance of the second wire connecting the semiconductor laser element and the transmission line. Therefore, a wide bandwidth can be achieved even with a bias T.

[0014] The block may further comprise a resistor connected in parallel with the inductor, in which case dips associated with parasitic capacitances can be reduced.

[0015] The optical semiconductor module may further include an RC series circuit, and the inductor may be connected between the RC series circuit and the transmission line, thereby further reducing the transmission dip.

[0016] The block may be disposed adjacent to the substrate inside the housing, in which case the block on which the inductor is mounted can be disposed adjacent to the substrate.

[0017] The dielectric constant of the low-k material may be smaller than that of the insulator of the substrate, in which case the parasitic capacitance can be further reduced by the dielectric constant of the low-k material of the block being smaller than that of the insulator of the substrate.

[0018] The inductance of the first wire may be at least twice as large as the inductance of the second wire, thereby achieving an even wider bandwidth.

[0019] [Details of the embodiment of the present disclosure] Specific examples of optical semiconductor modules according to embodiments of the present disclosure will be described with reference to the drawings. Note that the present invention is not limited to these examples, but is intended to include all modifications within the scope of the claims and equivalents thereto. In the description of the drawings, the same or corresponding elements are given the same reference numerals, and duplicated descriptions are omitted as appropriate. In addition, the drawings are partially simplified or exaggerated for ease of understanding, and the dimensional ratios and the like are not limited to those shown in the drawings.

[0020] (First embodiment) FIG. 1 is a plan view showing a schematic internal structure of an optical semiconductor module 1 according to a first embodiment. The optical semiconductor module 1 includes, for example, a rectangular housing 2 and an external terminal 3 provided at one end of the housing 2 in a direction D1, which is a longitudinal direction of the housing 2. The external terminals 3 are arranged along a direction D2, which is a width direction of the housing 2, at one end of the housing 2 in the direction D1. The external terminals 3 include, for example, a terminal for receiving a high-speed electric signal from the outside, a terminal for receiving a driving current of the laser diode, a terminal for receiving a driving current of the TEC, a monitor terminal for detecting the temperature of the laser diode, and a terminal for applying a ground potential (reference potential). The housing 2 has an inner wall 2b that defines an internal space S of the housing 2. An optical output unit 4 for outputting light L (optical transmission signal) is provided at an end of the housing 2 opposite to the external terminal 3 in the direction D1.

[0021] The optical semiconductor module 1 includes, for example, a transmission line 5, a pad 6 which is a DC pad, and a TEC (Thermo Electric Cooler) 7 which is a temperature control element, in the internal space S of the housing 2. FIG. 2 is a schematic plan view in which the upper structure of the TEC 7 is enlarged. As shown in FIGS. 1 and 2, the optical semiconductor module 1 includes the TEC 7, an AlN (Aluminum Nitride) substrate 8 (substrate) on which a semiconductor laser element 10 is mounted, and a block 9 on which an inductor 15 is placed. The transmission line 5 and the pad 6 are formed on the inner surface of the housing 2. The transmission line 5 and the pad 6 are connected to the external terminal 3 by wiring that penetrates the inner wall 2b. The wiring that connects each of the transmission line 5 and the pad 6 to the external terminal 3 is formed by, for example, metal plating or vapor deposition. The transmission line 5 includes a signal wiring 5s that extends in one direction at a certain distance from a ground wiring 5g that runs parallel to the transmission line 5 and a ground wiring 5g.

[0022] For example, the AlN substrate 8 is laminated on the TEC 7. The housing 2 accommodates, for example, the TEC 7, the AlN substrate 8, the block 9, the semiconductor laser element 10, and the inductor 15 in the internal space S. The TEC 7 has a temperature control surface 7b. The temperature control surface 7b is located opposite to the heat sink surface 7a on which the TEC 7 is mounted in the housing 2. For example, the heat sink surface 7a and the temperature control surface 7b are planes parallel to the direction D1 and the direction D2. More specifically, the AlN substrate 8 is mounted on the temperature control surface 7b in contact with the temperature control surface 7b. The AlN substrate 8 has a first surface 8b opposite to the TEC 7, and the semiconductor laser element 10 is placed on the first surface 8b. The block 9 is juxtaposed with the AlN substrate 8 on the TEC 7. The TEC 7 performs, for example, temperature control of the semiconductor laser element 10. For example, when a predetermined current is passed through the TEC 7, heat is absorbed at the temperature control surface 7b, and the absorbed heat is discharged at the heat sink surface 7a. At this time, the semiconductor laser element 10 is cooled through the AlN substrate 8. Also, for example, when a current is passed through the TEC 7 in a direction opposite to the predetermined current, heat is absorbed at the heat sink surface 7a, and the absorbed heat is discharged at the temperature control surface 7b. At this time, the semiconductor laser element 10 is heated through the AlN substrate 8. The block 9 is made of a low dielectric constant material. For example, the block 9 is made of quartz. The AlN substrate 8 includes, for example, an insulator, and the relative dielectric constant of the low dielectric constant material of the block 9 is smaller than the relative dielectric constant of the insulator of the AlN substrate 8. The semiconductor laser element 10 is, for example, an electro-absorption modulator integrated laser (EML). For example, the semiconductor laser element 10 includes a laser diode 10b and an optical modulator 10c (modulator).

[0023] FIG. 3 is a side view showing the block 9 and the inductor 15. As shown in FIG. 2 and FIG. 3, the block 9 has a second surface 9b facing the inductor 15, and a wiring 9c is formed on the second surface 9b. The block 9 is placed on the temperature control surface 7b of the TEC 7, for example, in contact with the temperature control surface 7b. The block 9 is placed on the inner surface of the housing 2, with the heat sink surface 7a in contact with the inner surface of the housing 2. The second surface 9b is, for example, a plane parallel to the direction D1 and the direction D2. The wiring 9c includes, for example, a first wiring 9d provided on the external terminal 3 side and a second wiring 9f provided on the optical output unit 4 side. The first wiring 9d and the second wiring 9f are insulated from each other. In addition, a resistor 16 is mounted on the second surface 9b, and the resistor 16 is, for example, disposed between the first wiring 9d and the second wiring 9f. In addition, the resistor 16 is electrically connected between the first wiring 9d and the second wiring 9f. The inductor 15 is electrically connected between the first wiring 9d and the second wiring 9f. That is, one end of the inductor 15 is connected to the first wiring 9d, and the other end of the inductor 15 is connected to the second wiring 9f. Therefore, the resistor 16 is connected in parallel with the inductor 15. Furthermore, the optical semiconductor module 1 includes an RC series circuit 17, and the inductor 15 is disposed between the RC series circuit 17 and a transmission line 11 described later. The inductor 15 functions as, for example, a bias T. The bias T supplies a bias (DC potential) to the transmission line 11. The bias becomes a reference potential of a high-frequency signal propagating through the transmission line 11. The bias T has a high impedance at high frequencies when viewed from the transmission line 11, and the influence on the high-frequency signal is suppressed to be small. The inductor 15 is mounted on the first wiring 9d and the second wiring 9f. For example, an electrode at one end of the inductor 15 is soldered to the first wiring 9d, and an electrode at the other end of the inductor 15 is soldered to the second wiring 9f. The RC series circuit may be configured, for example, by forming a pad 6 for mounting a resistor and a pad 6 for mounting a capacitor on the inner surface of the housing 2 and connecting these pads with wiring. The wiring connecting these pads may be formed by plating or vapor deposition.

[0024] The AlN substrate 8 has a transmission line 11 on a first surface 8b opposite to the TEC 7. The transmission line 11 includes a high-frequency wiring 11b extending in one direction (D1 direction) while maintaining a certain distance from a ground wiring 11c running in parallel. For example, the ground wiring 11c includes a first ground wiring portion 11d on which a die 12, a chip 13, and a resistor 14 are mounted, and a second ground wiring portion 11f located on the opposite side of the first ground wiring portion 11d as viewed from the high-frequency wiring 11b. The ground wiring 11c does not have to be a wiring extending in one direction like the transmission line 11, and may be a wide wiring pattern having a portion maintaining a certain distance from the transmission line.

[0025] Wires W1, W2, W3, and W4 extend from the die 12, the first ground wiring portion 11d, the high-frequency wiring 11b, and the second ground wiring portion 11f, respectively. For example, the optical semiconductor module 1 further includes a wire W5 that connects the die 12 and the laser diode 10b to each other, a wire W6 that connects one end of the resistor 14 to the modulator 10c to each other, and a wire W7 that connects the high-frequency wiring 11b and the modulator 10c to each other.

[0026] Furthermore, the optical semiconductor module 1 includes a wire W8 that connects the RC series circuit 17 and the inductor 15 to each other, and a wire W9 that connects the inductor 15 and the transmission line 11 to each other. The wires W1, W2, W3, W4, W5, W6, W7, W8, and W9 are, for example, bonding wires. The diameters of the wires W1, W2, W3, W4, W5, W6, W7, W8, and W9 are, for example, 18 μm, 25 μm, or 50 μm. In this case, the diameters of the wires W1, W2, W3, W4, W5, W6, W7, W8, and W9 may all be the same value, or may be different values ​​from each other. Note that the wires W1, W2, W3, W4, W5, W6, W7, W8, and W9 may be ribbon wires instead of bonding wires. The ribbon wire has, for example, a flat cross section, not a circular cross section like the bonding wire. For example, the width of the cross section is more than twice the thickness of the cross section. Wire W9 corresponds to a first wire connecting inductor 15 and transmission line 11 to each other. Wire W7 corresponds to a second wire connecting semiconductor laser element 10 and transmission line 11 to each other. The inductance of wire W9 is greater than the inductance of wire W7. For example, wire W9 may be longer than wire W7. Also, the cross-sectional area of ​​wire W9 (diameter, for example) may be smaller than the cross-sectional area of ​​wire W7.

[0027] Second embodiment Next, an optical semiconductor module 21 according to a second embodiment will be described with reference to FIG. 4. Since some of the configuration of the optical semiconductor module 21 according to the second embodiment overlaps with some of the configuration of the optical semiconductor module 1 described above, the same reference numerals as the elements of the optical semiconductor module 1 will be used to appropriately omit the description of the overlapping parts. As shown in FIG. 4, in the optical semiconductor module 21, the block 9 has a transmission line 22 on the second surface 9b. The transmission line 22 includes a high-frequency wiring 22b extending in one direction at a certain distance from a ground wiring 22c running in parallel. The ground wiring 22c includes, for example, a third ground wiring portion 22d and a fourth ground wiring portion 22f located on the opposite side of the third ground wiring portion 22d as viewed from the high-frequency wiring 22b. For example, in the optical semiconductor module 21, the AlN substrate 8 has only the first ground wiring portion 11d.

[0028] The optical semiconductor module 21 further includes a wire W10 that connects, for example, the third ground wiring portion 22d formed on the block 9 and the first ground wiring portion 11d formed on the AlN substrate 8 to each other. In the optical semiconductor module 21, the wire W9 extending from the inductor 15 is connected to the transmission line 22, and the wire W7 connects the high-frequency wiring 22b and the modulator 10c to each other. As in the optical semiconductor module 1 described above, the inductance of the wire W9 is larger than the inductance of the wire W7.

[0029] Next, the effects and advantages obtained from the optical semiconductor modules 1, 21 according to the above-mentioned embodiments will be described. First, in the optical semiconductor module 1 according to the first embodiment, as illustrated in FIG. 2, the AlN substrate 8 has the transmission line 11, and the block 9 is equipped with the inductor 15. The semiconductor laser element 10 is mounted on the AlN substrate 8. The block 9 is made of a low dielectric constant material. Therefore, the parasitic capacitance of the wiring 9c formed on the second surface 9b can be reduced. In addition, the inductance of the wire W9 connecting the inductor 15 and the transmission line 11 to each other is larger than the inductance of the wire W7 connecting the semiconductor laser element 10 and the transmission line 11 to each other. Since the inductance of the wire W9 connecting the inductor 15 and the transmission line 11 to each other is large, even in the presence of the inductor 15, the influence on the high-frequency signal propagating through the high-frequency wiring 11b can be suppressed, and the optical semiconductor module 1 can be made wider in bandwidth.

[0030] In the optical semiconductor module 21 according to the second embodiment, as illustrated in FIG. 4, the block 9 has a transmission line 22, and the inductor 15 is mounted on the block 9. The semiconductor laser element 10 is mounted on an AlN substrate 8. In the optical semiconductor module 21, the block 9 is made of a low dielectric constant material, as in the optical semiconductor module 1, so that the parasitic capacitance of the wiring 9c formed on the second surface 9b can be reduced. In addition, the inductance of the wire W9 connecting the inductor 15 and the transmission line 22 to each other is greater than the inductance of the wire W7 connecting the semiconductor laser element 10 and the transmission line 22 to each other. Therefore, even in the presence of the inductor 15, the effect on the high-frequency signal propagating through the high-frequency wiring 22b can be suppressed, and the optical semiconductor module 21 can be made wider in bandwidth.

[0031] Fig. 5 is a diagram showing an equivalent circuit of the bias T of the optical semiconductor module 1 (or the optical semiconductor module 21). The bias T includes, for example, a wire W9, an inductor 15, a resistor 16, and an RC series circuit 17. Fig. 6 is an equivalent circuit that simplifies the equivalent circuit of Fig. 5. As shown in Figs. 5 and 6, the inductance of the wire W9 is L, the resistance of the resistor 16 is R, para , the resistance of the RC series circuit 17 is R dump , and furthermore, R = R para +R dump Then, the resonant frequency ω0 of the series circuit of this inductance L and the RC parallel circuit is expressed as shown in equation (1).

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[0032] In this embodiment, the block 9 further includes a resistor 16 connected in parallel to the inductor 15. Therefore, the damping effect of the resistor 16 can reduce a dip associated with the parasitic capacitance.

[0033] In this embodiment, the optical semiconductor module 1 (or the optical semiconductor module 21) further includes an RC series circuit 17, and the inductor 15 is connected between the RC series circuit 17 and the transmission line 11 (or the transmission line 22). In this case, the transmission dip can be further reduced.

[0034] In this embodiment, the block 9 is disposed on the temperature control surface 7b of the TEC 7 adjacent to the AlN substrate 8. Therefore, the block 9 on which the inductor 15 is mounted can be disposed adjacent to the AlN substrate 8. This allows the inductor 15 to be disposed adjacent to the transmission line 11 formed on the AlN substrate 8. Furthermore, the transmission line 22 may be formed on the second surface 9b of the block 9. In this case, the inductor 15 can be disposed adjacent to the transmission line 22. The AlN substrate 8 and the block 9 are mounted on the temperature control surface 7b of the TEC 7, for example. However, when the semiconductor laser element 10 does not require temperature control, the AlN substrate 8 and the block 9 may be directly mounted on the inner surface of the housing 2.

[0035] In this embodiment, the dielectric constant of the low dielectric constant material of the block 9 is smaller than the dielectric constant of the insulator of the AlN substrate 8. Therefore, since the dielectric constant of the low dielectric constant material of the block 9 is smaller than the dielectric constant of the insulator of the AlN substrate 8, the parasitic capacitance can be further reduced. In this case, the thickness of the AlN substrate 8 may be made approximately the same as the thickness of the block 9. This makes it possible to reliably reduce the parasitic capacitance of the wiring connected to the inductor 15 compared to the case where the inductor 15 is mounted on the AlN substrate 8.

[0036] In this embodiment, the inductance of the wire W9 may be more than twice as large as the inductance of the wire W7, thereby achieving a further broadening of the bandwidth.

[0037] Next, an embodiment will be described. The present invention is not limited to the following embodiment. The optical semiconductor module according to the embodiment is the optical semiconductor module 1 described above, and includes a resistor 16 arranged in parallel with an inductor 15, and an RC series circuit 17, as shown in FIG. 5. FIG. 7 shows an equivalent circuit for a bias T of an optical semiconductor module according to a reference example. As shown in FIG. 7, the optical semiconductor module according to the reference example does not have a configuration equivalent to the resistor 16 and the RC series circuit 17.

[0038] The results of simulating the transmission characteristics of the transmission line 11 in each of the optical semiconductor modules of the above-mentioned Examples and Reference Example are shown in Fig. 8. As shown in Fig. 8, in the optical semiconductor module of the Reference Example that does not have the resistor 16 and the RC series circuit 17, a large resonance dip (transmission dip) appeared at a frequency of about 30 GHz. In contrast, in the optical semiconductor module of the Example, it was found that almost no resonance dip occurred, as in the case where no bias T was present. Note that the bias T is necessary to provide a reference potential for the high-frequency signal propagating through the transmission line, and the fact that the equivalent characteristics do not deteriorate even when a bias T is present, compared to the case where no bias T is present, is an example showing that the Example is more useful than the Reference Example.

[0039] Fig. 9 shows the results of simulating the transmission characteristics when the inductance of the wire W9 is changed in the optical semiconductor module according to the embodiment. As shown in Fig. 9, when the inductance of the wire W9 is 300 pH, some dips and high-frequency losses occur. In contrast, when the inductance of the wire W9 is 600 pH or more (600 pH or 1.2 nH), it was found that almost no dips or high-frequency losses occur, similar to the case where no bias T is provided.

[0040] The above describes the embodiments and examples of the optical semiconductor module according to the present disclosure. However, the present invention is not limited to the above-described embodiments or examples. In other words, it will be easily recognized by those skilled in the art that various modifications and changes are possible within the scope of the gist of the present invention as described in the claims.

[0041] For example, in the above-described embodiment, the optical semiconductor module 1 and the optical semiconductor module 21 are described as including the resistor 16 and the RC series circuit 17, as exemplified in Fig. 5. However, an optical semiconductor module may not include the RC series circuit 17, as shown in Fig. 10, for example. In this manner, at least one of the resistor 16 and the RC series circuit 17 may be omitted.

[0042] In the above embodiment, an example has been described in which the die 12, the chip 13, and the resistor 14 are mounted on the transmission line 11. However, the type and number of elements mounted on the transmission line 11 are not limited to the above example and can be changed as appropriate. In the above embodiment, an example has been described in which the semiconductor laser element 10 is an EML. However, the semiconductor laser element may be a semiconductor laser element other than an EML.

[0043] In the above embodiment, an example was described in which the substrate was an AlN substrate 8 and the block 9 was a quartz substrate. However, the substrate may be made of a material other than AlN. The block may be made of alumina, FPC, or polyimide. In other words, the materials of the substrate and block are not particularly limited as long as the dielectric constant of the low dielectric constant material of the block 9 is smaller than the dielectric constant of the insulator of the substrate. [Explanation of symbols]

[0044] 1,21...Opto-semiconductor module 2. Housing 2b…Inner wall 3...External terminal 4...Optical output section 5...Transmission line 6. Pad 7…TEC 7a…Heat sink surface 7b…Temperature control surface 8...AlN substrate (substrate) 8b…Side 1 9…Block 9b…Second side 9c…Wiring 9d…First wiring 9f…Second wiring 10...Semiconductor laser element 10b...Laser diode 10c…Modulator 11,22...Transmission lines 11b, 22b...High frequency wiring 11c, 22c...Ground wiring 11d…First ground wiring section 11f…Second ground wiring section 12…Die 13. Tip 14. Resistance 15…Inductor 16…Resistance 17...RC series circuit 22d…Third ground wiring section 22f…4th ground wiring section D1,D2…direction L…Light S…interior space W1, W2, W3, W4, W5, W6, W7, W8, W9, W10…Wire

Claims

1. a substrate having a transmission line and a semiconductor laser element mounted thereon; a block on which an inductor is mounted, the block being made of a low dielectric constant material having a dielectric constant smaller than that of the insulator of the substrate; a housing that houses the substrate and the block; Equipped with the transmission line includes a high-frequency wiring extending in a first direction while maintaining a constant distance from a ground wiring running in parallel therewith; the inductor is connected to the high-frequency wiring via a first wire; the semiconductor laser element is connected to the high-frequency wiring via a second wire, The inductance of the first wire is greater than the inductance of the second wire. Optical semiconductor module.

2. A substrate on which a semiconductor laser element is mounted; a block made of a low dielectric constant material having a dielectric constant smaller than the dielectric constant of the insulator of the substrate, the block having a transmission line and an inductor mounted thereon; a housing that houses the substrate and the block; Equipped with the transmission line includes a high-frequency wiring extending in a first direction while maintaining a constant distance from a ground wiring running in parallel therewith; the inductor is connected to the high-frequency wiring via a first wire; the semiconductor laser element is connected to the high-frequency wiring via a second wire, The inductance of the first wire is greater than the inductance of the second wire. Optical semiconductor module.

3. The block further comprises a resistor connected in parallel with the inductor.

3. The optical semiconductor module according to claim 1.

4. Further comprising an RC series circuit, the inductor is connected between the RC series circuit and the high-frequency wiring of the transmission line; The optical semiconductor module according to claim 1 .

5. the block is disposed adjacent to the substrate and inside the housing; The optical semiconductor module according to claim 1 .

6. The block is made of quartz. The optical semiconductor module according to claim 1 .

7. The inductance of the first wire is at least twice the inductance of the second wire. The optical semiconductor module according to claim 1 .

8. The housing has a longitudinal direction in the first direction. The optical semiconductor module according to claim 1 .

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