JP2023044435A - optical module - Google Patents

Abstract

To provide an optical module which enables multiple optical semiconductor devices to be heated efficiently.SOLUTION: An optical module according to one embodiment includes: a housing having a first terminal and a second terminal; multiple optical semiconductor devices which are installed along a first direction on an inner surface of the housing and respectively emit signal lights; and multiple heater members which are respectively mounted on upper parts of the multiple optical semiconductor devices and generate heat through energization. The multiple heater members are electrically connected through multiple bonding wires between the first terminal and the second terminal so as to be serially connected with the first terminal and the second terminal.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to optical modules.

Patent documents 1 and 2 describe optical semiconductor laser modules. The optical semiconductor laser module of Patent Document 1 includes a 1.3 μm band FP type semiconductor laser, a Pt thin film heater, a temperature control module, a Si submount, a temperature sensor, and a temperature control module. A heater is sandwiched between the submount and the semiconductor laser, and the heater raises the temperature of the semiconductor laser. A temperature sensor senses the temperature of the semiconductor laser. The temperature control module controls the heater so that the temperature of the semiconductor laser is higher than room temperature.

JP-A-2001-94200 JP 2021-120987 A

By the way, in the case of an optical module including a plurality of optical semiconductor devices and a plurality of heaters, wiring for each of the plurality of heaters may be required. Concerned. That is, since heat escapes from each of the plurality of heaters through wires, the amount of heat generated by the heaters must be increased, and the plurality of optical semiconductor devices may not be efficiently heated.

An object of the present disclosure is to provide an optical module capable of efficiently heating a plurality of optical semiconductor devices.

An optical module according to the present disclosure includes a housing having a first terminal and a second terminal, a plurality of optical semiconductor devices installed along a first direction on the inner surface of the housing, and emitting signal light, respectively; and a plurality of heater members each mounted on an upper portion of each of the optical semiconductor devices and generating heat when energized. The plurality of heater members are electrically connected between the first terminal and the second terminal via a plurality of bonding wires so as to be in series connection with the first terminal and the second terminal, respectively.

According to the present disclosure, it is possible to efficiently heat a plurality of optical semiconductor devices.

FIG. 1 is a plan view showing the internal structure of the optical module according to the embodiment. 2 is a partial cross-sectional view showing an optical semiconductor device, a carrier, a base, a heat insulating block and a housing of the optical module of FIG. 1. FIG. FIG. 3 is a diagram showing a heater member, a carrier, a base, and a housing of the optical module according to the embodiment; FIG. 4 is a diagram showing a heater member, an optical semiconductor device, a carrier, a base, a heat insulating block, a housing, and bonding wires of the optical module according to the embodiment; FIG. 5 is a diagram showing a heater member, an optical semiconductor device, a carrier, a base, a heat insulating block, a housing, and bonding wires of an optical module according to the first modified example. FIG. 6 is a diagram showing the heater member, carrier, housing, and bonding wires of the optical module according to the second modification. 7 is a perspective view showing the heater member of FIG. 6. FIG. 8 is a perspective view of the heater member in FIG. 6 viewed from a direction different from that in FIG. 7. FIG. FIG. 9 is a perspective view showing how the heater member of FIG. 7 is mounted on the optical semiconductor device.

[Description of Embodiments of the Present Disclosure]
First, embodiments of the optical module according to the present disclosure will be listed and described. An optical module according to one embodiment includes a housing having a first terminal and a second terminal, a plurality of optical semiconductor devices installed along a first direction on the inner surface of the housing and emitting signal light, respectively; and a plurality of heater members that are mounted on respective upper portions of the plurality of optical semiconductor devices and generate heat when energized. The plurality of heater members are electrically connected between the first terminal and the second terminal via a plurality of bonding wires so as to be in series connection with the first terminal and the second terminal, respectively.

In this optical module, the housing has a first terminal and a second terminal. The optical module includes a plurality of optical semiconductor devices arranged along the first direction on the inner surface of the housing, and a plurality of heater members arranged above each of the plurality of optical semiconductor devices. A plurality of heater members are arranged between the first terminal and the second terminal. The first terminal, the plurality of heater members, and the second terminal are electrically connected to each other in series via each of the plurality of bonding wires. Therefore, since the plurality of heater members are connected in series between the first terminal and the second terminal, it is possible to prevent heat from escaping from the heater members to the housing as compared with the case where the heater members are connected in parallel. . Therefore, the amount of heat generated from the heater member can be suppressed, and the plurality of optical semiconductor devices can be efficiently heated.

Each of the plurality of optical semiconductor devices may be mounted on the inner surface of the housing via a heat insulating block, and the thermal conductivity of the heat insulating block may be lower than that of the housing. In this case, since the heat insulation block is interposed between each optical semiconductor device and the inner surface of the housing, heat escaping from each optical semiconductor device to the housing can be reduced.

The plurality of heater members may include a first heater member, a second heater member, a third heater member arranged at one end in the first direction, and a fourth heater member arranged at the other end in the first direction. The first heater member is electrically connected to the first terminal, the second heater member is electrically connected to the second terminal, and the first heater member and the second heater member are connected to the third heater member and the fourth heater member. It may be arranged between the heater member. The first heater member and the second heater member tend to become hotter than the third heater member and the fourth heater member located at one end and the other end in the first direction, respectively. In this optical module, the first heater member arranged between the third heater member and the fourth heater member is electrically connected to the first terminal, and the second heater member is electrically connected to the second terminal. ing. In this case, heat can be efficiently released to the first terminal and the second terminal from the first heater member and the second heater member, which tend to reach high temperatures. Therefore, the temperatures of the plurality of heater members can be made nearly uniform.

The first heater member and the second heater member may be arranged adjacent to each other. The third heater member may be electrically connected to the fourth heater member via one of the plurality of bonding wires. In this case, the temperatures of the first heater member, the second heater member, the third heater member, and the fourth heater member can be made nearly uniform.

Each of the plurality of heater members may comprise a heater having first heater terminals and second heater terminals. The first heater terminals and the second heater terminals of the first heater member and the second heater member may be arranged so as to line up along the first direction. The first heater terminals and the second heater terminals of the third heater member and the fourth heater member may be arranged side by side along a second direction intersecting the first direction. In this case, wiring to each heater terminal of each heater member can be efficiently performed so that a plurality of bonding wires do not interfere with each other.

The plurality of heater members generate heat by current flowing between the first heater terminal and the second heater terminal, and the resistance values of the heaters of the first heater member and the second heater member are the same as those of the third heater member and the fourth heater member. may be smaller than the resistance value of the heater. In this case, the resistance values of the heaters of the first heater member and the second heater member connected to the first terminal and the second terminal of the housing, respectively, are higher than the resistance values of the heaters of the third heater member and the fourth heater member. is also small. Therefore, the resistance values of the heaters of the first heater member and the second heater member connected to the housing are small, so that the heat efficiency of the plurality of heater members can be maintained high.

Each of the plurality of heater members may have a front surface on which the heater, the first heater terminals and the second heater terminals are provided, and a rear surface facing away from the front surface. Each heater member may be electrically connected to each optical semiconductor device via a via extending from the front surface to the back surface and a back surface electrode formed on the back surface. In this case, each heater member can be electrically connected to each optical semiconductor device through the via and the back electrode.

[Details of the embodiment of the present disclosure]
A specific example of an optical module according to an embodiment of the present disclosure will be described below with reference to the drawings. It should be noted that the present invention is not limited to the following examples, but is intended to include all modifications indicated in the scope of claims and within the scope equivalent to the scope of claims. In the description of the drawings, the same reference numerals are given to the same or corresponding elements, and overlapping descriptions are omitted as appropriate. In addition, the drawings may be partially simplified or exaggerated for easy understanding, and the dimensional ratios and the like are not limited to those described in the drawings.

FIG. 1 is a diagram showing the internal structure of an optical module 1 according to this embodiment. As shown in FIG. 1, the optical module 1 is an optical transmitter module (TOSA: Transmitter Optical Sub Assembly) including a rectangular parallelepiped housing 2 and a cylindrical optical coupling portion 3 having a flange. Inside the optical module 1, N (N is a natural number of 2 or more) optical semiconductor devices 11 and a multiplexing optical system 20 are provided. As an example, the optical module 1 is a 4-channel (N=4) optical transmission module. Four channels correspond to four optical signals having different peak wavelengths. The optical module 1 can transmit mutually independent information for each channel. Therefore, the optical module 1 can transmit a large amount of information as the number of channels increases.

The optical module 1 includes N carriers 12 for N optical semiconductor devices 11 . One optical semiconductor device 11 is mounted on one carrier 12 . Each optical semiconductor device 11 emits a laser beam. Each optical semiconductor device 11 is mounted on the carrier 12 so that the directions (optical axes) of the laser beams emitted by the respective optical semiconductor devices 11 are parallel to each other. The carrier 12 is a substrate that is made of, for example, aluminum nitride (AlN) and is resistant to thermal expansion. The carrier 12 may be made of ceramics or an insulating material other than aluminum nitride. Alternatively, the carrier 12 may be made of an insulating material other than ceramics. The housing 2 also has an internal space 2A and a feedthrough 2B. The feedthrough 2B penetrates the rear wall (rear wall) of the housing 2 . The internal space 2A is defined in the second direction D2 and the first direction D1 by a front wall (front wall) of the housing 2, a rear wall, and two side walls connecting the front wall and the rear wall. N optical semiconductor devices 11 and N carriers 12 are accommodated in internal space 2A. A portion of the feedthrough 2B is exposed outside the housing 2 . The exposed portion of the feedthrough 2B is provided with a plurality of terminals 6 arranged side by side for electrical connection with an external device. Also, the feedthrough 2B has a portion facing the internal space 2A of the housing 2 . A portion of the feedthrough 2B facing the internal space 2A is provided with, for example, a plurality of terminals 4 and N signal lines 5 constituting transmission lines. The transmission line is, for example, a coplanar line or a microstrip line. The N signal lines 5 and the plurality of terminals 4 are electrically connected to corresponding terminals 6, respectively.

The optical module 1 is configured such that each optical semiconductor device 11 functioning as a light source is independently driven. For example, when N=4, the N optical semiconductor devices 11 emit signal lights L1, L2, L3, and L4 having different peak wavelengths. One optical semiconductor device 11 emits one of four channels of signal light L1, L2, L3, and L4. The optical axes of the signal lights L1, L2, L3, and L4, for example, extend parallel to each other. A drive signal to the optical semiconductor device 11 is provided from the outside of the optical module 1, for example. The drive signal is transmitted to the optical semiconductor device 11 via the feedthrough 2B and the signal line 5. FIG.

The signal lights L1, L2, L3, and L4 are lights modulated according to drive signals. The signal lights L1, L2, L3, and L4 have peak wavelengths different from each other. The optical semiconductor device 11 has, for example, a monolithic optical integrated circuit. The optical semiconductor device 11 has, for example, a laser diode. A multiplexing optical system 20 generates one light L from N optical signals. For example, when N=4, the combining optical system 20 combines the signal lights L1, L2, L3, and L4, and couples the light L obtained by combining to the optical coupling section 3. FIG. Light L is, for example, a wavelength division multiplexing signal. The multiplexing optical system 20 includes, for example, N lenses, a beam splitter, a mirror and a polarization combiner. An optical coupling section 3 is provided on the front wall (front wall) of the housing 2 . The optical coupling portion 3 can be connected to an optical connector (not shown) provided at the tip of the optical fiber. The light L multiplexed by the multiplexing optical system 20 is output to the optical fiber through the optical coupling section 3 . Regarding directions, the direction in which the light L is output from the optical module 1 may be referred to as front, front, or forward, and the direction opposite to front, front, or front may be referred to as rear, rear, or rear. However, these directions are for convenience of explanation, and do not limit the directions in which the parts are arranged.

FIG. 2 is a partial cross-sectional view of the housing 2 showing components mounted on the inner surface 2b of the housing 2 facing the internal space 2A. FIG. 3 is a plan view schematically showing the inner surface 2b of the housing 2. FIG. As shown in FIGS. 2 and 3, the inner surface 2b of the housing 2 is provided with the aforementioned N optical semiconductor devices 11 and N carriers 12, a heat insulation block 13, and a base . The heat insulating block 13 is mounted on the inner surface 2b. The thermal conductivity of the heat insulation block 13 is smaller than that of the housing 2 . Moreover, the heat insulation block 13 has insulation. For example, the heat insulating block 13 is made of a glass-based material. The heat insulating block 13 has a rectangular parallelepiped shape. The heat insulation block 13 has a plurality of long sides extending along a first direction D1 that is the width direction of the housing 2, a plurality of short sides extending along a second direction D2 orthogonal to the first direction D1, and a first and a plurality of short sides extending along a third direction D3 orthogonal to both the direction D1 and the second direction D2. The second direction D2 corresponds to the longitudinal direction of the housing 2, for example. Also, for example, the direction along the optical axis of the light L output from the optical module 1 described above corresponds to the second direction D2. In the following description, the side of the inner surface 2b viewed from the heat insulating block 13 may be referred to as the bottom, the bottom, or the bottom, and the side opposite to the inner surface 2b (the side of the optical semiconductor device 11) viewed from the heat insulating block 13 may be referred to as the top. , may be referred to as upper or upper. However, these directions are for convenience of explanation, and do not limit the directions in which the parts are arranged.

The base 14 is mounted on the top surface of the heat insulation block 13 . The base 14 has a thin plate shape with a plurality of long sides extending along the first direction D1, a plurality of short sides extending along the second direction D2, and a plurality of short sides extending along the third direction D3. The base 14 is made of ceramic, for example. N carriers 12 are mounted on the upper surface of the base 14 . That is, a heat insulating block 13 and a base 14 are arranged between the inner surface 2 b and the N carriers 12 .

FIG. 4 is a diagram schematically showing a cross section when the optical module 1 is cut along a plane perpendicular to the second direction D2. The optical module 1 includes N heater members 30 . The N heater members 30 are arranged side by side along the first direction D1. The N heater members 30 are mounted, for example, on the N optical semiconductor devices 11 one by one. The housing 2 has, for example, a pair of side portions 2c arranged along the first direction D1 and a bottom portion 2j having an inner surface 2b. The pair of side portions 2c are provided inside side walls (not shown) of the housing 2, for example. In addition, the pair of side portions 2c may be formed as part of the side walls, respectively. A first terminal 2f is provided on one upper surface of the pair of side portions 2c, and a second terminal 2h is provided on the other upper surface of the pair of side portions 2c. The side portion 2c is a ceramic substrate for wiring, for example, the material of the side portion 2c is different from the material of the bottom portion 2j. The material of the bottom portion 2j is, for example, copper tungsten or copper molybdenum. The internal space 2A of the housing 2 is defined in the third direction D3 by the inner surface 2b and the inner surface of the lid (not shown). The lid is joined to the front wall, rear wall and two side walls of the housing 2 to seal the internal space 2A of the housing 2 .

The first terminal 2f, the plurality of heater members 30, and the second terminal 2h are electrically connected to each other via the plurality of bonding wires W, respectively. The plurality of bonding wires W are, for example, a first bonding wire W1 that electrically connects the first terminal 2f and the heater member 30 to each other, and a second bonding wire that electrically connects the second terminal 2h and the heater member 30 to each other. W2, and a third bonding wire W3 electrically connecting the N heater members 30 adjacent to each other. For example, the number of bonding wires W is at least N+1.

The N heater members 30 include, for example, a first heater member 31, a second heater member 32, a third heater member 33 and a fourth heater member 34 when N=4. For example, the third heater member 33 is provided at a position adjacent to the first terminal 2f in the first direction D1, and the fourth heater member 34 is provided at a position adjacent to the second terminal 2h in the first direction D1. The first heater member 31 and the second heater member 32 are provided between the third heater member 33 and the fourth heater member 34 . The first heater member 31 and the second heater member 32 are adjacent to each other.

For example, the first heater member 31 is adjacent to the third heater member 33 and the second heater member 32 is adjacent to the fourth heater member 34 in the first direction D1. The third heater member 33 is electrically connected to the first terminal 2f via the first bonding wire W1, and the fourth heater member 34 is electrically connected to the second terminal 2h via the second bonding wire W2. It is The first heater member 31 is electrically connected to the third heater member 33 via one third bonding wire W3. The second heater member 32 is electrically connected to the first heater member 31 via one third bonding wire W3. The fourth heater member 34 is electrically connected to the second heater member 32 via one third bonding wire W3.

Next, functions and effects obtained from the optical module 1 according to the embodiment will be described. In the optical module 1, the housing 2 has a first terminal 2f and a second terminal 2h. The optical module 1 includes a plurality of optical semiconductor devices 11 arranged along the first direction D1 on the inner surface 2b of the housing 2, and a plurality of heater members 30 arranged above the plurality of optical semiconductor devices 11. Prepare. A plurality of heater members 30 are arranged between the first terminal 2f and the second terminal 2h. The first terminal 2f, the plurality of heater members 30, and the second terminal 2h are electrically connected to each other in series via the plurality of bonding wires W, respectively. Therefore, since the plurality of heater members 30 are connected in series between the first terminal 2f and the second terminal 2h, heat escapes from the heater members 30 to the housing 2 compared to the case of parallel connection. can be made difficult. Therefore, the amount of heat generated from the heater member 30 can be suppressed, and the plurality of optical semiconductor devices 11 can be efficiently heated.

In the embodiment, each of the plurality of optical semiconductor devices 11 is mounted on the inner surface 2b of the housing 2 via a heat insulating block 13, and the thermal conductivity of the heat insulating block 13 is higher than that of the housing 2. small. In this case, since the heat insulating block 13 is interposed between each optical semiconductor device 11 and the inner surface of the housing 2, the amount of heat that escapes from each optical semiconductor device 11 to the housing 2 can be reduced.

Next, an optical module according to the first modified example will be described with reference to FIG. A part of the configuration of the optical module according to the modification is the same as a part of the configuration of the optical module 1 described above. Therefore, in the following description, the same reference numerals are given to the portions that overlap with the configuration of the optical module 1, and the description thereof will be omitted as appropriate.

As shown in FIG. 5, the optical module according to the first modification differs from the optical module 1 in the form of wiring in the plurality of heater members 30 . The first heater member 31 is electrically connected to the first terminal 2f via the first bonding wire W1, and the second heater member 32 is electrically connected to the second terminal 2h via the second bonding wire W2. It is The first bonding wire W1 extends above the third heater member 33 in the first direction D1, and the second bonding wire W2 extends above the fourth heater member 34 in the first direction D1.

The third bonding wires W3 are arranged between the first heater member 31 and the third heater member 33, between the third heater member 33 and the fourth heater member 34, between the second heater member 32 and the fourth heater member 34, provided in each of the The third heater member 33 is electrically connected to each of the first heater member 31 and the fourth heater member 34 via each of the two third bonding wires W3. The fourth heater member 34 is electrically connected to each of the second heater member 32 and the third heater member 33 via each of the two third bonding wires W3. The third bonding wire W3 connecting the third heater member 33 to the fourth heater member 34 and the third bonding wire W3 connecting the fourth heater member 34 to the third bonding wire W3 are the same.

As described above, in the optical module according to the first modification, the first terminal 2f, the plurality of heater members 30, and the second terminal 2h are electrically connected in series with each other through the plurality of bonding wires W. , effects similar to those of the optical module 1 described above can be obtained. By the way, the first heater member 31 and the second heater member 32 tend to become hotter than the third heater member 33 and the fourth heater member 34 located at one end and the other end in the first direction D1, respectively. be. For example, when the four heater members from the first heater member 31 to the fourth heater member 34 generate the same Joule heat, the first heater member 31 and the second heater member 32 are adjacent to each other in the first direction D1. Since there is a heater member at the bottom, heat is less likely to escape to the surroundings than the third heater member 33 and the fourth heater member 34, which have heater members adjacent to each other only on one side. Therefore, since it is difficult for heat to escape to the surroundings, it is efficiently heated by the Joule heat generated by itself, and the temperature tends to rise.

In the optical module according to the first modification, the first heater member 31 arranged between the third heater member 33 and the fourth heater member 34 is electrically connected to the first terminal 2f, and the second heater member 32 is electrically connected to the first terminal 2f. is electrically connected to the second terminal 2h. In this case, heat can be efficiently released to the first terminal 2f and the second terminal 2h from the first heater member 31 and the second heater member 32, which tend to reach high temperatures. Therefore, the temperatures of the plurality of heater members 30 can be made nearly uniform. As a specific example, when the same Joule heat is generated in four heater members from the first heater member 31 to the fourth heater member 34, in the optical module 1 described above, the first heater member 31 and the second heater member 32 The temperature was 0.8 degrees higher than the temperatures of the third heater member 33 and the fourth heater member 34 . On the other hand, when Joule heat is similarly generated, in the optical module according to the first modification, the temperatures of the first heater member 31 and the second heater member 32 and the temperatures of the third heater member 33 and the fourth heater member The temperature difference with the temperature of 34 can be lowered to 0.4 degrees.

The first heater member 31 and the second heater member 32 are arranged adjacent to each other. W3) are electrically connected. Therefore, the temperatures of the first heater member 31, the second heater member 32, the third heater member 33, and the fourth heater member 34 can be made nearly uniform.

Next, an optical module according to a second modified example will be described with reference to FIG. As shown in FIG. 6 , the optical module according to the second modification comprises N capacitors 16 , each capacitor 16 being mounted on each carrier 12 . Each heater member 30 includes a heater 41 , a first heater terminal 42 and a second heater terminal 43 that supply current to the heater 41 , and an electrode 44 . The heater 41 generates heat by current flowing between the first heater terminal 42 and the second heater terminal 43 . The heater 41 is made of, for example, a material having electrical resistance. The heater 41 is, for example, a resistive element.

For example, the heater 41 has a rectangular shape when viewed from the third direction D3. Each of the first heater terminal 42 and the second heater terminal 43 is electrically connected to the heater 41 . The first heater terminals 42 and the second heater terminals 43 are arranged along the longitudinal direction of the heater 41 (the direction in which the long side of the heater 41 extends). The electrode 44 is arranged between the first heater terminal 42 and the second heater terminal 43 . The electrode 44 is an electrode for supplying power to the optical semiconductor device 11 . Each electrode 44 is electrically connected to each capacitor 16 via a fourth bonding wire W4.

The housing 2 includes a side portion 2k positioned on the second direction D2 side of the N carriers 12, and a first terminal 2f and a second terminal 2h are arranged on the upper surface of the side portion 2k. The side portion 2k may be a portion facing the internal space 2A of the feedthrough 2B, and the first terminal 2f and the second terminal 2h are provided, for example, in a portion facing the internal space 2A of the feedthrough 2B. may be arranged as part of a plurality of terminals 4 that are connected to each other. Each of the first heater member 31 and the second heater member 32 is arranged such that the first heater terminals 42 and the second heater terminals 43 are arranged along the first direction D1. Each of the third heater member 33 and the fourth heater member 34 is arranged such that the first heater terminals 42 and the second heater terminals 43 are aligned along the second direction D2.

A first bonding wire W1 extends in the second direction D2 from the second heater terminal 43 of the first heater member 31, and a second bonding wire W2 extends from the first heater terminal 42 of the second heater member 32 in the second direction. It extends in direction D2. The first bonding wire W1 is connected to the first terminal 2f, and the second bonding wire W2 is connected to the second terminal 2h. A third bonding wire W3 extends from the first heater terminal 42 of the first heater member 31 in the first direction D1. A third bonding wire W3 extending from the first heater terminal 42 of the first heater member 31 is connected to the first heater terminal 42 of the third heater member 33 .

A third bonding wire W3 extends from the second heater terminal 43 of the second heater member 32 in the first direction D1. A third bonding wire W3 extending from the second heater terminal 43 of the second heater member 32 is connected to the first heater terminal 42 of the fourth heater member 34 . A third bonding wire W3 extends from the second heater terminal 43 of the third heater member 33 in the first direction D1. A third bonding wire W3 extending from the second heater terminal 43 of the third heater member 33 is connected to the second heater terminal 43 of the fourth heater member 34 .

FIG. 7 is a perspective view showing the configuration of each of the first heater member 31, the second heater member 32, the third heater member 33 and the fourth heater member 34. FIG. FIG. 8 is a perspective view of the configuration of each of the first heater member 31, the second heater member 32, the third heater member 33, and the fourth heater member 34, viewed from a direction different from that of FIG. The configurations of the first heater member 31, the second heater member 32, the third heater member 33, and the fourth heater member 34 are, for example, the same. Therefore, in the following description, the first heater member 31, the second heater member 32, the third heater member 33, and the fourth heater member 34 are collectively described as the heater member 30 when there is no need to distinguish between them.

The heater member 30 has a front surface 30b on which the heater 41, the first heater terminal 42, the second heater terminal 43 and the electrode 44 are provided, and a back surface 30c facing away from the front surface 30b. The first heater terminal 42, the second heater terminal 43 and the electrode 44 are made of metal. Heater member 30 has vias 45 extending from surface 30b to back surface 30c, and back electrode 46, which is a metal portion metallized on back surface 30c. The back surface electrode 46 is formed, for example, on the entire surface of the back surface 30c. A via 45 is interposed between the electrode 44 and the back electrode 46 , and the electrode 44 and the back electrode 46 are electrically connected to each other through the via 45 . The via 45 is made of metal. The heater member 30 has, for example, a rectangular parallelepiped shape. The distance (thickness) between the front surface 30b and the rear surface 30c of the heater member 30 is smaller than the length of the long side and short side of the rectangle when the front surface 30b and the rear surface 30c are rectangular in shape. The heater member 30 has, for example, ceramics as a main material (base material). A body portion of the heater member 30 excluding the heater 41, the first heater terminal 42, the second heater terminal 43, the electrode 44, and the via 45 is made of ceramics, for example. Electrode 44 is electrically insulated from first heater terminal 42 and second heater terminal 43 .

FIG. 9 is a perspective view showing the optical semiconductor device 11 and the heater member 30 mounted on the carrier 12. FIG. As shown in FIGS. 7 to 9, for example, a plurality of (for example, four) pillars 11c are provided on the top surface 11b of the optical semiconductor device 11, and the back electrode 46 of the heater member 30 is connected to the plurality of pillars 11c. , the back electrode 46 of the heater member 30 is electrically connected to the optical semiconductor device 11 via the plurality of pillars 11c. Further, the heater member 30 can be fixed to the optical semiconductor device 11 by bonding the back electrode 46 of the heater member 30 to the plurality of pillars 11c. The mode of electrical connection between the heater member 30 and the optical semiconductor device 11 is not limited to the pillars 11c, and the optical semiconductor device 11 may be electrically connected to the heater member 30 via solder bumps. The Joule heat generated by the heater 41 is conducted to the optical semiconductor device 11 via the main body, back surface 30c, and pillars 11c (or solder bumps) of the heater member 30, thereby raising the temperature of the optical semiconductor device 11. FIG. The thermal resistance of the path through which heat is transmitted from the heater 41 to the optical semiconductor device 11 through the plurality of bonding wires W is made greater than the thermal resistance of the path through which heat is transmitted from the heater 41 (heat is less likely to be transmitted). Thus, heat loss can be reduced, and the optical semiconductor device 11 can be efficiently heated.

As described above, in the optical module according to the second modification, each of the plurality of heater members 30 includes the heater 41 having the first heater terminal 42 and the second heater terminal 43 . The first heater terminals 42 and the second heater terminals 43 of the first heater member 31 and the second heater member 32 are arranged along the first direction D1. The first heater terminals 42 and the second heater terminals 43 of the third heater member 33 and the fourth heater member 34 are arranged side by side along the second direction D2. Therefore, wiring to each heater terminal of each heater member can be efficiently performed so that a plurality of bonding wires W do not interfere with each other.

That is, the position of the third bonding wire W3 extending from the first heater member 31 to the third heater member 33 and the third bonding wire W3 extending from the second heater member 32 to the fourth heater member 34 in the second direction D2 and the The positions of the third bonding wires W3 extending from the third heater member 33 to the fourth heater member 34 in the second direction D2 are different from each other. As a result, the bonding wires W do not overlap when viewed from the third direction D3. The possibility that W overlaps can be further reduced.

Each of the plurality of heater members 30 has a front surface 30b on which the heater 41, the first heater terminals 42 and the second heater terminals 43 are provided, and a back surface 30c facing away from the front surface 30b. Each heater member 30 is electrically connected to each optical semiconductor device 11 via a via 45 extending from the surface 30b to the back surface 30c and a back surface electrode 46 formed on the back surface 30c. Therefore, each heater member 30 can be electrically connected to each optical semiconductor device 11 through the via 45 and the back electrode 46 . Further, the heater member 30 can be fixed to the optical semiconductor device 11 by joining the back electrode 46 to the plurality of pillars 11c. For example, the length (thickness) of the heater member 30 in the third direction D3 is smaller than the lengths in the first direction D1 and the second direction D2, and the heater member is made of a material having high thermal conductivity. The thermal resistance from 41 to each optical semiconductor device 11 can be reduced. Thereby, the optical semiconductor device 11 can be efficiently heated.

Next, an optical module according to a third modification will be described with reference to FIGS. 5 and 7. FIG. As shown in FIG. 5, the layout of the components of the optical module according to the third modification is, for example, the same as the layout of the components of the optical module according to the first modification. In the third modification, the resistance values of the heaters 41 of the first heater member 31 and the second heater member 32 are smaller than the resistance values of the heaters 41 of the third heater member 33 and the fourth heater member 34 .

As described above, when the heater 41 has a rectangular shape, the resistance value of the heater 41 changes depending on the width (the length in the lateral direction) of the heater 41 . That is, the wider the width of the heater 41 is, the smaller the resistance value of the heater 41 is, and the narrower the width of the heater 41 is, the larger the resistance value of the heater 41 is. For example, the width of each heater 41 of the first heater member 31 and the second heater member 32 is wider than the width of each heater 41 of the third heater member 33 and the fourth heater member 34 .

As described above, in the third modification, the plurality of heater members 30 generate heat due to the current flowing between the first heater terminals 42 and the second heater terminals 43, and the first heater members 31 and the second heater members 32 are heated. The resistance value of the heater 41 is smaller than the resistance values of the heaters 41 of the third heater member 33 and the fourth heater member 34 . Therefore, the resistance values of the heaters 41 of the first heater member 31 and the second heater member 32 connected to the first terminal 2f and the second terminal 2h of the housing 2 are the third heater member 33 and the fourth heater member 34, respectively. is smaller than the resistance value of the heater 41 of . Therefore, since the resistance values of the heaters 41 of the first heater member 31 and the second heater member 32 connected to the housing 2 are small, the amount of heat generated by the first heater member 31 and the second heater member 32 is reduced to that of the third heater member. 33 and the amount of heat generated by the fourth heater member 34 (the electric currents flowing through the heaters 41 of the first heater member 31 to the fourth heater member 34 are the same). As described above, the first heater member 31 and the second heater member 32 tend to reach higher temperatures than the third heater member 33 and the fourth heater member 34, so the temperatures of the first heater member 31 and the second heater member 32 are It is possible to prevent the heater member from becoming higher than the third heater member 33 and the fourth heater member 34 . As a result, the temperatures of the first heater member 31 to the fourth heater member 34 are made uniform, and the amounts of heat generated by the first heater member 31 and the second heater member 32 are moderately reduced, so that the optical semiconductor device 11 can be operated efficiently. Can be heated.

In the third modified example, an example in which the resistance value of the heater 41 is changed has been described. However, instead of changing the resistance value of the heater 41, the number of bonding wires W may be changed. For example, the number of third bonding wires W3 may be doubled (the number of third bonding wires W3 connecting two heater members to each other may be two). Also in this case, since the number of the third bonding wires W3 is increased, the mutual thermal conductivity between the first heater member 31 to the fourth heater member 34 is improved, and the respective temperatures are made uniform. By improving the accuracy of temperature control, the optical semiconductor device 11 can be efficiently heated. Further, instead of doubling the number of the third bonding wires W3, the thickness of the third bonding wires W3 may be changed. For example, the third bonding wire W3 may be thicker than the first bonding wire W1 and the second bonding wire W2. Also in this case, the same effect as described above can be obtained.

The embodiment and various modifications according to the present disclosure have been described above. However, the present invention is not limited to the above-described embodiments or various modifications, and can be appropriately modified within the scope of the claims. Also, the optical module according to the present disclosure may be a combination of multiple examples of the above-described embodiment, first modified example, second modified example, and third modified example. Further, in the above-described embodiment, the optical module 1, which is an optical transmission module including the rectangular parallelepiped housing 2 and the columnar optical coupling portion 3 having the flange, has been described. However, the shapes and the like of the housing and the optical coupling portion are not limited to the shapes and the like of the housing 2 and the optical coupling portion 3 and can be changed as appropriate. Also, the optical module may not be an optical transmitter module, but may be, for example, an optical receiver module.

DESCRIPTION OF SYMBOLS 1... Optical module 2... Housing 2A... Internal space 2B... Feed through 2b... Inner surface 2c... Side part 2f... First terminal 2h... Second terminal 2j... Bottom part 2k... Side part 3... Optical coupling part 4, 6... Terminal REFERENCE SIGNS LIST 5 signal line 11 optical semiconductor device 11b upper surface 11c pillar 12 carrier 13 heat insulating block 14 base 16 capacitor 20 multiplexing optical system 30 heater member 30b front surface 30c rear surface 31 first heater member 32... Second heater member 33... Third heater member 34... Fourth heater member 41... Heater 42... First heater terminal 43... Second heater terminal 44... Electrode 45... Via 46... Back surface electrode

Claims (8)

a housing having a first terminal and a second terminal;
a plurality of optical semiconductor devices that are installed along the first direction on the inner surface of the housing and that respectively emit signal light;
a plurality of heater members mounted on respective upper portions of the plurality of optical semiconductor devices and each generating heat when energized;
with
The plurality of heater members are electrically connected via a plurality of bonding wires between the first terminal and the second terminal so as to be connected in series with the first terminal and the second terminal, respectively. there is
optical module. Each of the plurality of optical semiconductor devices is mounted on the inner surface of the housing via a heat insulating block,
The thermal conductivity of the heat insulating block is smaller than the thermal conductivity of the housing,
The optical module according to claim 1. The plurality of heater members includes a first heater member, a second heater member, a third heater member arranged at one end in the first direction, and a fourth heater member arranged at the other end in the first direction. and
The first heater member is electrically connected to the first terminal,
The second heater member is electrically connected to the second terminal,
The first heater member and the second heater member are arranged between the third heater member and the fourth heater member,
3. The optical module according to claim 1 or 2. The first heater member and the second heater member are arranged adjacent to each other,
The optical module according to claim 3. The third heater member is electrically connected to the fourth heater member via one of the plurality of bonding wires,
The optical module according to claim 3 or 4. each of the plurality of heater members includes a heater having a first heater terminal and a second heater terminal;
the first heater terminals and the second heater terminals of the first heater member and the second heater member are arranged along the first direction,
The first heater terminals and the second heater terminals of the third heater member and the fourth heater member are arranged so as to line up along a second direction that intersects with the first direction,
The optical module according to any one of claims 3 to 5. the plurality of heater members generate heat by current flowing between the first heater terminal and the second heater terminal;
the resistance values of the heaters of the first heater member and the second heater member are smaller than the resistance values of the heaters of the third heater member and the fourth heater member;
The optical module according to claim 6. each of the plurality of heater members has a surface on which the heater, the first heater terminal and the second heater terminal are provided, and a back surface facing away from the surface;
each heater member is electrically connected to each optical semiconductor device via a via extending from the front surface to the back surface and a back surface electrode formed on the back surface;
The optical module according to claim 6 or 7.

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