JP5663944B2 - Optical semiconductor device and flexible substrate - Google Patents

Description

  The present invention relates to a flexible substrate and an optical semiconductor device including the same.

  An optical semiconductor device includes an optical element that performs signal conversion between an optical signal and an electrical signal. The optical element is housed in a housing in the optical semiconductor device, and the housing has a plurality of input / output terminals for inputting / outputting electric signals to / from the outside.

  In order to connect the wiring to the input / output terminals of the casing, a method using a flexible substrate is known. The flexible substrate is made of a material that is thinner and more flexible than an ordinary printed circuit board, and a plurality of signal lines are formed on the substrate. The flexible substrate is fixed, for example, perpendicularly to the housing, and input / output terminals (lead wires) of the housing are soldered to the signal lines through holes formed in the flexible substrate. Such an optical semiconductor device is described in Patent Document 1, for example.

JP 2006-332648 A

  In the above optical semiconductor device, the input / output terminals are configured in two stages in order to cope with an increase in the number of input / output terminals. However, even if the number of input / output terminals is increased in this way, it is not easy to increase the number of input / output terminals on the flexible substrate side due to the limitation of the width. It can be avoided by connecting a flexible substrate corresponding to each of the terminals. However, when a flexible substrate is connected to each of the input / output terminals configured in two stages, the high-frequency signal is deteriorated due to the difference in signal characteristics between the high-frequency signal lines.

  The present invention has been made in view of the above problems, and an object thereof is to provide a flexible substrate with improved signal transmission characteristics and an optical semiconductor device including the flexible substrate.

The optical semiconductor device includes an optical element, and is provided to be opposed to each other in two upper and lower rows , and includes a plurality of first terminals arranged in one row and a plurality of second terminals arranged in one row. A housing provided with, a first region in which a first wiring electrically connected to the first terminal is formed, a second region in which a second wiring electrically connected to the second terminal is formed, A flexible substrate having a third region connecting between the first region and the second region, and the third region has one through-hole through which the first terminal or the second terminal passes. It is characterized by being formed in a row.

In the above configuration, the first wiring includes a high-frequency signal that forms a signal transmission path with a ground potential, and the second wiring includes only a signal line that does not form a signal transmission path with the ground potential. You may go out.

The said structure WHEREIN: The through-hole which the said 1st terminal and the said 2nd terminal penetrate may each be formed in the said 3rd area | region in 1 row.

In the above configuration, the printed circuit board further includes a printed circuit board having a first surface and a second surface facing the first surface, wherein the first region is connected to a terminal provided on the first surface, and the second region is It can be set as the structure connected with the terminal provided in the 2nd surface.

The flexible substrate includes a plurality of signal lines that do not constitute a signal transmission path between a first region including a first wiring including a plurality of high-frequency signal lines that constitute a signal transmission path between the ground potential and the ground potential. A second region provided with a second wiring including, and a third region located between the first region and the second region and folded back so that the first region and the second region face each other. seen including, in the third region, the through holes corresponding to said first wiring or the second wiring, and characterized by being formed in each one column.

In the above configuration, the second wiring may include only a signal line that does not form a signal transmission path with the ground potential. The said structure WHEREIN: The through-hole corresponding to the said 1st wiring and the said 2nd wiring may each be formed in the said 3rd area | region in 1 row.

  According to the present optical semiconductor device, signal transfer characteristics can be improved.

1 is an overall view of an optical semiconductor device according to Example 1. FIG. 1 is a diagram illustrating a configuration of a flexible substrate according to Example 1. FIG. It is a figure which shows the state by which the flexible substrate which concerns on Example 1 was connected to the housing | casing. It is a figure which shows the state by which the flexible substrate which concerns on Example 1 was connected to the housing | casing and the printed circuit board. It is a figure which shows the state by which the flexible substrate which concerns on Example 2 was connected to the housing | casing. It is a figure which shows the state by which the flexible substrate which concerns on Example 2 was connected to the housing | casing and the printed circuit board. 7 is a diagram illustrating a configuration of a flexible substrate according to Example 3. FIG. It is a figure which shows the state by which the flexible substrate which concerns on Example 3 was connected to the housing | casing. 6 is a diagram illustrating a configuration of a flexible substrate according to Example 4. FIG. It is a figure which shows the state by which the flexible substrate which concerns on Example 4 was connected to the housing | casing. FIG. 10 is a diagram illustrating a configuration of a flexible substrate according to a modification example of Example 4. FIG. 10 is a diagram illustrating a configuration of a flexible substrate according to Example 5. It is a figure which shows the state by which the flexible substrate which concerns on Example 5 was connected to the housing | casing. It is a figure which shows the state by which the flexible substrate which concerns on the modification of Example 5 was connected to the housing | casing. FIG. 10 is a diagram illustrating a configuration of a flexible substrate according to Example 6. It is a figure which shows the state by which the flexible substrate based on Example 6 was connected to the housing | casing.

  FIG. 1 is a schematic cross-sectional view illustrating the entire configuration of the optical semiconductor device according to the first embodiment. The optical semiconductor device 100 includes a housing 60, a housing 10, an insulator 11, a first flexible substrate 20a, a second flexible substrate 20b, and a printed circuit board 30. The housing 10 uses a re-sectorable 40. In the following description, the direction in which the optical connector 70 of the optical semiconductor device 100 is inserted is the X direction, and the plane perpendicular to the X direction in the plane of the printed circuit board 30 is the Y direction, the X direction, and the Y direction. A horizontal plane and a direction perpendicular to the surface of the printed circuit board 30 are defined as a Z direction (vertical direction). The basic configuration of the optical semiconductor device 100 is common to all the embodiments (Examples 1 to 6), but the part related to the configuration of the flexible substrate is different for each embodiment.

  An optical element (for example, a light emitting element or a light receiving element, a lens, a TEC, a driver IC, a thermistor, and a wavelength detection unit) that performs signal conversion between an optical signal and an electric signal is disposed inside the housing 10. (Not shown). The optical element outputs an optical signal controlled by the high frequency signal and the direct current signal to the optical connector 70. Inside the housing 10, internal wiring for transmitting a signal for controlling the optical element is provided (not shown). The internal wiring includes a high-frequency signal line that transmits a high-frequency signal and a DC signal line that transmits a DC signal. The housing 10 is provided with a first input / output terminal 12a and a second input / output terminal 12b for inputting / outputting signals to / from the outside. The first input / output terminal 12a and the second input / output terminal 12b are provided in two separate upper and lower stages so as to extend in the longitudinal direction (X direction) of the housing 10. In this embodiment, a plurality of the first input / output terminals 12a and the second input / output terminals 12b are arranged on the same horizontal plane, but the number of each terminal may be an arbitrary number of 1 or more. it can. In addition, each arbitrary terminal can be an input terminal or an output terminal, and similarly, any terminal can be a high-frequency signal terminal or a DC signal terminal.

  FIG. 2A is a top view of the first flexible substrate 20a, and FIG. 2B is a top view of the second flexible substrate 20b. The first flexible board 20a and the second flexible board 20b are wiring boards made of a thin and flexible material (for example, a material containing polyimide), and can be bent freely. On the surface of the first flexible substrate 20a, a high-frequency signal line RF that forms a signal transmission path with the ground potential and a signal line that does not form a signal transmission path with the ground potential (hereinafter referred to as a DC signal). Although referred to as a line DC, a plurality of drive power lines and detection signal lines are formed in this signal line. A ground pattern (not shown) having a ground potential is formed on the back surface of the first flexible substrate 20a. The metallization ML of the signal line and the ground pattern is formed from a material containing, for example, Cu (copper). The high-frequency signal line RF and the direct-current signal line DC are formed in parallel to each other so as to extend in the longitudinal direction (X direction) of the first flexible substrate 20a. On the second flexible substrate 20b, only a plurality of DC signal lines DC are formed, and no high-frequency signal lines are formed. The DC signal lines DC are formed in parallel to each other so as to extend in the longitudinal direction (X direction) of the second flexible substrate 20b. The first flexible substrate 20a and the second flexible substrate 20b have a connection portion 18 in which the width of the portion connected to the input / output terminal is wider than that of the signal line. In addition, although not shown in figure, this connection part 18 is provided in both ends. The DC signal line DC includes an optical element driving power line, an optical element power detection element signal line, an optical element wavelength detection signal line, a temperature control device driving power line, and a temperature detection element signal. Line, driver IC drive power supply line, reference potential signal line, and the like.

  FIG. 3 is a diagram illustrating a state in which the first flexible substrate 20 a and the second flexible substrate 20 b are connected to the housing 10. The first flexible substrate 20a and the second flexible substrate 20b are connected to the casing 10 so as to face each other (so as to overlap each other when viewed from the top and bottom direction), and the lengths are equal. The high-frequency signal line RF and the DC signal line DC on the first flexible substrate 20a are connected to the input / output terminal 12a of the housing 10, and the DC signal line DC on the second flexible substrate 20b is connected to the input / output terminal 12b of the housing 10. Each is connected. Here, the extending direction of the input / output terminals (12a, 12b) in the connection portion is equal to the extending direction of each signal line formed on the first flexible substrate 20a and the second flexible substrate 20b. As is apparent from FIG. 3, the first flexible substrate 20a and the second flexible substrate 20b provide separate flexible drawers. That is, it can be said that the second flexible substrate 20b provides a flexible drawer different from the first flexible substrate 20a.

  FIG. 4 is a diagram illustrating a state in which the first flexible substrate 20 a and the second flexible substrate 20 b are connected to the housing 10 and the printed circuit board 30. The printed circuit board 30 is a wiring board made of a material that is thicker and harder than the flexible boards (20a, 20b). A high-frequency signal line and a DC signal line are formed on the lower surface, and a DC signal line is formed on the upper surface. Yes. A first flexible substrate 20 a is connected to the lower surface of the printed circuit board 30, and a second flexible substrate 20 b is connected to the upper surface of the printed circuit board 30. The high-frequency signal line RF on the first flexible substrate 20a is connected to the high-frequency signal line on the lower surface of the printed circuit board 30, and the DC signal line DC on the first flexible substrate 20a is connected to the DC signal line on the lower surface of the printed circuit board 30. . The DC signal line DC on the second flexible substrate 20 b is connected to the DC signal line DC on the upper surface of the printed board 30. Further, the high-frequency signal line and the DC signal line formed on the printed circuit board 30 are connected to the outside of the optical semiconductor device 100.

  A high-frequency signal input from the outside is input to the inside of the housing 10 via a high-frequency signal line RF formed on the lower surface of the printed circuit board 30 and the first flexible substrate 20a. Similarly, a DC signal input from the outside is a DC signal line DC formed on the lower surface of the printed circuit board 30 and the first flexible substrate 20a, or a DC signal formed on the upper surface of the printed circuit board 30 and the second flexible substrate 20b. The signal is input into the housing 10 through the line DC. When an electrical signal is output from the housing 10 to the outside, the signal is transmitted in the reverse direction.

  According to the optical semiconductor device 100 according to the first embodiment, the two flexible substrates (20a, 20b) are connected to the two input / output terminals (12a, 12b) of the housing 10 so as to face each other. A plurality of signal lines (RF, DC) are formed on each flexible substrate, and are connected to the plurality of signal lines in the input / output terminals (12a, 12b). According to this configuration, by connecting flexible boards to both sides of the printed circuit board 30, many signal lines can be formed in a small space, so that the number of signal lines that can be input and output to the housing is increased. be able to.

  Further, according to the optical semiconductor device 100, the high-frequency signal line RF and the direct-current signal line DC are formed on the first flexible substrate 20a, and the direct-current signal line DC is formed on the second flexible substrate 20b. In other words, the high-frequency signal line RF is formed only on the first flexible substrate 20a and is not formed on the second flexible substrate 20b. In order to suppress the deterioration of the high-frequency signal due to the difference in signal characteristics between the terminals, among the plurality of first input / output terminals 12a and second input / output terminals 12b protruding from the housing 10 in two rows, for high-frequency signals These terminals are preferably formed in one of the rows. By forming the high frequency signal lines together on the same flexible substrate as in this embodiment, it is possible to suppress the difference in signal characteristics between the high frequency signal lines. Note that a driver IC, a preamplifier, or the like may be disposed inside the housing 10 according to the first embodiment.

  Example 2 is an example in which flexible substrates having different lengths are used.

  FIG. 5 is a schematic cross-sectional view illustrating a state in which the flexible substrates (20a, 20b) according to the second embodiment are connected to the housing 10. In the second embodiment, the length of the second flexible substrate 20b on which only the DC signal line DC is formed is larger than the length of the first flexible substrate 20a on which the high-frequency signal line RF is formed. Other configurations are the same as those of the first embodiment (FIG. 3), and detailed description thereof is omitted. Here, the length of the flexible substrate refers to the length of the flexible substrate (20a, 20b) in the extending direction (X direction) of the signal lines (high-frequency signal lines and DC signal lines).

  FIG. 6 is a diagram showing a state in which the flexible boards (20a, 20b) are connected to the printed board 30. FIG. As shown in the drawing, a via 34 is formed in the connection portion 32 of the first flexible substrate 20a. By this via 34, the metallized ML provided on both surfaces is electrically connected. The second flexible substrate 20b is greatly curved compared to the first flexible substrate 20a. That is, the maximum curvature of the second flexible substrate 20b is larger than the maximum curvature of the second flexible substrate 20b.

  According to the optical semiconductor device 100 of the second embodiment, the lengths of the two flexible boards (20a, 20b) are different, and therefore the position when the flexible boards (20a, 20b) are connected to the housing 10 and the printed board 30. An alignment margin can be secured. Thereby, the position shift which generate | occur | produces when connecting a flexible substrate (20a, 20b) can be suppressed.

  In the case where the lengths of the flexible substrates (20a, 20b) are different, either the first flexible substrate 20a or the second flexible substrate 20b may be lengthened. However, since the high-frequency signal is more easily affected by the curvature of the signal line than the direct-current signal, the second flexible substrate in which the high-frequency signal line RF is not formed (only the direct-current signal line DC is formed) as in this embodiment. The length of 20b is preferably larger than the length of the first flexible substrate 20a on which the high-frequency signal line RF is formed. In other words, the maximum curvature of the second flexible substrate 20b is preferably larger than the maximum curvature of the first flexible substrate 20a. From the above, after aligning the first flexible substrate 20a on which the high-frequency signal line RF is formed, the first flexible substrate 20a is aligned by aligning the second flexible substrate 20b on which only the DC signal line DC is formed. And the printed circuit board 30 and the first flexible circuit board 20a and the input / output terminal 12a of the housing 10 are connected at an accurate position. Thereby, the position shift of the high frequency signal line RF can be suppressed, and the deterioration of the signal transmission characteristics can be suppressed.

  Example 3 is an example in which the first flexible substrate and the second flexible substrate in Examples 1 and 2 are configured by a single flexible substrate. However, both the first flexible substrate and the second flexible substrate are the same as the first and second embodiments in that each provides another flexible drawer. That is, the flexible substrate 20b provides a flexible drawer different from the second flexible substrate 20a.

  FIG. 7 is a schematic top view illustrating the configuration of the flexible substrate used in the optical semiconductor device 100 according to the third embodiment. The flexible substrate 20 has three regions, a first region 22, a second region 24, and a third region 26. The length of the second region 24 in the X direction is larger than the length of the first region 22 in the X direction.

  The first region 22 is a region where a high-frequency signal line is formed, and plays the same role as the first flexible substrate 20a in the first and second embodiments. A plurality of high-frequency signal lines RF are formed in parallel at the central portion in the Y direction of the first region 22, and a plurality of DC signal lines DC are formed outside thereof in parallel to each other.

  The second region 24 is a region where a DC signal line is formed, and plays the same role as the second flexible substrate 20b in the first and second embodiments. In this embodiment, a plurality of DC signal lines DC are formed in parallel to each other.

  The third region 26 is a region located between the first region 22 and the second region 24 and is a region that becomes a curved portion when the flexible substrate 20 is bent as will be described later. In the following description, a case where a signal line is not formed in the third region 26 will be described, but a signal line may be formed in the third region 26.

  FIG. 8A is a plan view of the state in which the flexible substrate 20 is connected to the housing 10 as viewed from the lower side (the first region 22 side), and FIG. 8B is a view of A in FIG. It is sectional drawing along the -A line. The housing 10 includes a first input / output terminal 12a and a second input / output terminal 12b having a two-stage configuration, as in the first and second embodiments. The flexible substrate 20 is curved at the boundary between the first region 22 and the third region 26, and at the boundary between the second region 24 and the third region 26, and the first region 22 and the second region 24 face each other. ing. The lower surface of the first region 22 is connected to the upper surface of the input / output terminal 12a, and the upper surface of the second region 24 is connected to the lower surface of the input / output terminal 12b. That is, the flexible substrate 20 is connected inside the two input / output terminals (12a, 12b) by the connection portion 23 of the first region 22 and the connection portion 25 of the second region 24 provided outside the flexible substrate 20. Has been. As a connection method, for example, soldering can be used.

  The end of the flexible substrate 20 opposite to the side connected to the housing 10 is connected to the printed circuit board 30. As in the first and second embodiments, the first region 22 of the flexible substrate 20 is connected to the lower surface of the printed circuit board 30, and the second region 24 is connected to the upper surface of the printed circuit board 30. Since the connection method of the flexible substrate 20 and the printed circuit board 30 and the connection method of each signal line are the same as those described in the first and second embodiments, the drawings and detailed description are omitted in the following description.

  According to the optical semiconductor device according to the third embodiment, the same function as the first flexible substrate 20a and the second flexible substrate 20b in the first and second embodiments can be realized by one flexible substrate 20. That is, the number of input / output terminals can be increased by forming the flexible substrate 20 in a two-stage configuration. In addition, by forming the high-frequency signal line RF only in the first region 22 and making the length of the second region 24 larger than the length of the first region 22, it is possible to suppress deterioration of signal characteristics due to the curvature of the signal line. In addition, the alignment can be easily performed. In addition, when there are two flexible substrates, it is necessary to align the first flexible substrate 20a and the second flexible substrate 20b. However, in this embodiment, since there is one flexible substrate, the alignment is performed. It can be done more easily.

  Example 4 is an example in which a through hole is formed in the flexible substrate used in Example 3.

  FIG. 9 is a schematic top view illustrating the configuration of the flexible substrate 20 used in the optical semiconductor device 100 according to the fourth embodiment. Similar to the third embodiment, the flexible substrate 20 has three regions of a first region 22, a second region 24, and a third region 26. In the first region 22, a high-frequency signal line RF and a direct-current signal line DC are provided. The second region 24 is formed with a DC signal line DC. Unlike the third embodiment, a plurality of through holes 50 are formed in the third region 26. Other configurations are the same as those of the third embodiment, and detailed description thereof is omitted.

  In the third region 26, a plurality of through holes 50 are formed on the extended lines of the plurality of signal lines (RF, DC) formed in the first region 22 and the second region 24. In this embodiment, one through hole 50 is formed for each signal line, and as a result, two rows of through holes are formed at both ends of the third region 26. The diameter of the through hole 50 is as large as the width of each signal line. When the flexible substrate 20 is connected to the housing 10, the lead terminals of the signal lines constituting the input / output terminals 12 are inserted into the through holes 50 and connected to the signal lines.

  FIG. 10A is a plan view of the state in which the flexible substrate 20 is connected to the housing 10 as viewed from the lower side (the first region 22 side), and FIG. 10B is a diagram of A in FIG. It is sectional drawing along the -A line. As shown in FIG. 10A, the lead terminal of the input / output terminal 12 passes through the through hole 50 and is connected to the signal lines (RF, DC). 10B, the upper surface of the first region 22 is connected to the lower surface of the input / output terminal 12a, and the lower surface of the second region 24 is connected to the upper surface of the input / output terminal 12b. That is, the flexible substrate 20 is connected outside the two input / output terminals (12a, 12b) by the connecting portion 23 of the first region 22 and the connecting portion 25 of the second region 24 provided outside the flexible substrate 20. Has been.

  According to the optical semiconductor device 100 according to the fourth embodiment, the connection reliability is achieved by connecting the lead terminal of the input / output terminal 12 to the signal line (RF, DC) through the through hole provided in the flexible substrate 20. Can be increased. Further, by providing the through hole 50, the third region 26 of the flexible substrate 20 can be easily bent. Thereby, position shift of the flexible substrate 20 in areas other than the third area 26 (the first area 22 and the second area 24) can be suppressed, and deterioration of signal characteristics can be suppressed.

  In the above description, the through holes 50 are formed at both ends of the third region 26, but the through holes 50 may be formed only on one side of the third region 26.

  FIG. 11 is a diagram illustrating a modification of the flexible substrate 20. As shown in the figure, the through hole 50 is provided only on the second region 24 side, and is not provided on the first region 22 side. 9 is the same as FIG. 9 in that one through hole 50 is formed for each signal line (RF, DC) formed on the second region 24. Also in this configuration, the connection reliability can be improved by connecting the lead terminal of the input / output terminal 12 to the signal line (RF, DC) through the through hole 50. The flexible substrate 20 has two input terminals (12a, 12b) by a connection portion 25 of the second region 24 provided inside the flexible substrate 20 and a connection portion 23 of the first region 22 provided outside the flexible substrate 20. ). Further, by making the third region 26 of the flexible substrate 20 easy to be bent by the through hole 50, the bending of the flexible substrate 20 in the regions other than the third region 26 (the first region 22 and the second region 24) is suppressed, Deterioration of signal characteristics can be suppressed. In this modification, the through hole 50 is formed on the second region 24 side, but the through hole 50 may be formed on the first region 22 side.

  Example 5 is an example in which a larger through hole than that of Example 4 was formed.

  FIG. 12 is a schematic top view illustrating the configuration of the flexible substrate 20 used in the optical semiconductor device according to the fifth embodiment. Similar to the third to fourth embodiments, the flexible substrate 20 has three regions of a first region 22, a second region 24, and a third region 26, and the first region 22 has a high-frequency signal line RF and a DC signal line. A DC signal line DC is formed in each of the second regions 24.

  As shown in the drawing, in the flexible substrate 20 according to the present embodiment, a large through hole (hereinafter, cut-out portion 52) is formed in the central portion of the third region 26. The length of the cutout portion 52 in the X direction is substantially equal to the length of the third region 26 in the X direction, and the length of the cutout portion 52 in the Y direction is a length corresponding to a plurality of signal lines (RF, DC). It has become.

  In the present embodiment, the length of the high-frequency signal line RF in the first region 22 is formed to be larger than the length of the DC signal line DC in the first region 22. As a result, the high-frequency signal line RF slightly protrudes toward the third region 26 as compared with the direct-current signal line DC (reference numeral 28). Here, cut portions 54 communicating with the cutout portions 52 are formed at two positions on both ends of the protruding portion 28 on the Y direction side. Thereby, the through hole formed in the third region 26 has a U-shaped shape. Further, in the first region 22, the RF signal line connection portion 23 is formed long in the X direction.

  FIG. 13A is a plan view of the state in which the flexible substrate 20 is connected to the housing 10 as viewed from the lower side (first region 22 side). 13B is a cross-sectional view taken along the line AA in FIG. 13A, and FIG. 13C is a cross-sectional view taken along the line BB in FIG. is there.

  As shown in FIG. 13B, in the region where only the DC signal line DC is formed, the flexible substrate 20 is curved in the third region 26 as in the third to fourth embodiments, and has a substantially U-shape as a whole. It has become. On the other hand, as shown in FIG. 13C, in the region where the high-frequency signal line RF is formed, the first region 22 and the second region 24 are separated by the cutout portion 52, so that the flexible substrate 20 is curved. It is not connected to the housing 10 substantially horizontally. In the present embodiment, the flexible substrate 20 is connected inside the two terminals (12a, 12b) in the first region 22 and the second region 24 provided outside the flexible substrate 20.

  According to the optical semiconductor device 100 according to the fifth embodiment, since the through hole (cutout portion 52) is formed in the third region 26, the flexible substrate 20 can be easily bent in the third region 26. Thereby, the bending of the flexible substrate 20 other than the third region 26 can be suppressed, and the deterioration of the signal characteristics accompanying the bending of the signal line can be suppressed. In particular, since the size of the through hole is larger than that in the fourth embodiment by forming the through hole over a plurality of regions of the signal lines, the flexible substrate 20 can be more easily curved in the third region 26. Can do.

  Further, cut portions 54 along the signal line forming direction are provided at both ends of the protruding portion of the high frequency signal line RF, and the high frequency signal line RF is formed in the cut portion 52 and the protruding portion 28 partitioned by the cut portion 54. Thus, the bending of the high-frequency signal line RF can be suppressed. Thereby, characteristic deterioration of the high frequency signal which is easily affected by the bending of the signal line can be suppressed.

  FIGS. 14A to 14C are diagrams showing modifications of the fifth embodiment, and correspond to FIGS. 13A to 13C of the present embodiment, respectively. As shown in FIG. 14 (c), this embodiment is different from the present embodiment in that the protruding portion 28 of the first region 24 is connected to the lower surface of the input / output terminal 12. In addition, the flexible substrate 20 is connected to the lower surface of the input / output terminal 12 a by the connection portion 27 of the first region 22 provided inside the flexible substrate 20. Note that a via 29 is formed in the protruding portion 28 of the flexible substrate 20, and the input / output terminal 12 a and the signal line are connected via the via 29. In the present embodiment, the flexible substrate 20 and the input / output terminal 12a can be easily connected by forming the cut portion 54 of FIG. 12 deeply. Other configurations are the same as in this embodiment. When connecting the flexible substrate 20 to the housing 10, the flexible substrate 20 may be connected to either the upper surface or the lower surface of each input / output terminal (12a, 12b). Which surface is used can be appropriately selected according to the specifications of the product, the application direction of force in the manufacturing process, and the like.

  Example 6 is an example in which the through holes of the form of Example 4 and Example 5 are used in combination.

  FIG. 15 is a schematic top view illustrating the configuration of the flexible substrate 20 used in the optical semiconductor device according to the sixth embodiment. Similar to the third to fifth embodiments, the flexible substrate 20 has three regions of a first region 22, a second region 24, and a third region 26, and the first region 22 has a high-frequency signal line RF and a DC signal line. A DC signal line DC is formed in each of the second regions 24.

  As shown in the drawing, in the present embodiment, a cutout portion 52 and a cutout portion 54 similar to those in the fifth embodiment are formed in the central portion of the third region 26. Further, in the third region 26, a through hole 50 similar to that of the fourth embodiment is formed for each signal line in a region where the cutout portion 52 is not formed.

  FIG. 16A is a plan view of the state in which the flexible substrate 20 is connected to the housing 10 as viewed from the lower side (first region 22 side). 16B is a cross-sectional view taken along line AA in FIG. 16A, and FIG. 16C is a cross-sectional view taken along line BB in FIG. is there. As shown in FIG. 16B, in the region where only the DC signal line DC is formed, the flexible substrate 20 is curved in a U shape. As shown in FIG. 16C, in the region where the high-frequency signal line RF is formed, the flexible substrate 20 is connected to the housing 10 almost horizontally. The lead terminal of the input / output terminal 12 passes through the through hole 50 and is connected to each signal line (RF, DC).

  In the optical semiconductor device according to the sixth embodiment, the cutout portion 52 (the cutout portion 54) and the through hole 50 are used in combination to facilitate the bending in the third region 26 of the flexible substrate 20, and the signal lines in other regions. The curvature of (RF, DC) can be suppressed. Further, the connection stability can be improved by connecting the lead wire of the input / output terminal 12 to the signal line (RF, DC) via the through hole 50.

  The structural features in each embodiment are summarized as follows.

  As shown in the first to sixth embodiments, the input / output terminal 12 of the housing 10 has a two-stage configuration (12a, 12b), and signal lines (RF, DC) to the respective input / output terminals (12a, 12b). The number of signal lines can be increased by connecting the flexible substrate 20 formed with.

  Moreover, as shown in Examples 1 to 6, by forming the high-frequency signal lines RF together on a flexible substrate on the same plane, it is possible to suppress the difference in signal characteristics between the high-frequency signal lines, Deterioration of signal characteristics can be suppressed.

  Moreover, as shown in Examples 2 to 6, by making the lengths of the first flexible substrate and the second flexible substrate (in Examples 3 to 6 the first region and the second region) different, Positioning when connecting the flexible substrate to the housing can be easily performed. At this time, it is preferable to reduce the length of the flexible substrate (or region) on the side where the high-frequency signal line RF is formed in order to suppress deterioration of the high-frequency signal that is easily affected by the curvature of the signal line.

  Moreover, as shown in Examples 2-6, the lengths of the first flexible substrate and the second flexible substrate (in Examples 3-6, the first region and the second region) are different. Even if the lengths of the first flexible substrate and the second flexible substrate (the first region and the second region in Examples 3 to 6) are the same, the high-frequency signal lines RF are collectively formed on the flexible substrate on the same plane. Thus, it is possible to suppress the difference in signal characteristics between the high-frequency signals and to suppress the deterioration of the signal characteristics.

  Further, as shown in Examples 4 to 6, when one flexible substrate is bent and used, a through hole (at least one of the through hole 50 and the cutout portion 52) is formed in the third region. Thus, the flexible substrate can be easily bent. Further, the connection stability can be improved by connecting the lead wire to the signal line through the through hole. One through hole may be formed for each signal line as in the fourth embodiment, or through holes may be formed over a plurality of signal lines as in the fifth embodiment. Moreover, you may use these forms together like Example 6. FIG.

  In Examples 1-6, when connecting the flexible substrate 20 to the housing 10, the flexible substrate 20 may be connected to either the upper surface or the lower surface of each input / output terminal (12a, 12b). Which surface is used can be appropriately selected according to the specifications of the product, the application direction of force in the manufacturing process, and the like.

  The structural features of the above-described embodiments can be arbitrarily combined.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

DESCRIPTION OF SYMBOLS 10 Case 12 Input / output terminal 20 Flexible board 22 1st area | region 24 2nd area | region 26 3rd area | region 30 Printed circuit board 100 Optical semiconductor device RF High frequency signal line DC DC signal line

Claims (7)

A housing including a plurality of first terminals arranged in one row and a plurality of second terminals arranged in a row, the optical elements being built in, facing each other in two rows ;
A first region in which a first wiring electrically connected to the first terminal is formed; a second region in which a second wiring electrically connected to the second terminal is formed; the first region; A flexible substrate having a third region connecting between the second regions,
The optical semiconductor device, wherein the third region is formed with a through-hole through which the first terminal or the second terminal penetrates in a row . The first wiring includes a high-frequency signal that forms a signal transmission path with a ground potential,
  2. The optical semiconductor device according to claim 1, wherein the second wiring includes only a signal line that does not constitute a signal transmission path with respect to a ground potential. 3. The optical semiconductor device according to claim 1, wherein in the third region, through-holes through which the first terminal and the second terminal pass are formed in one row, respectively . The printed circuit board further includes a printed circuit board having a first surface and a second surface opposite to the first surface, the first region being connected to a terminal provided on the first surface, and the second region being the second surface. The optical semiconductor device according to claim 1, wherein the optical semiconductor device is connected to a terminal provided on the optical device. A first region including a first wiring including a plurality of high-frequency signal lines constituting a signal transmission path with respect to a ground potential;
A second region provided with a second wiring including a plurality of signal lines that do not constitute a signal transmission path with respect to the ground potential;
Located between the first region and the second region, viewed contains a third region in which the first region and the second region is folded to face,
The flexible substrate according to claim 3, wherein through holes corresponding to the first wiring or the second wiring are formed in a row in the third region . The flexible substrate according to claim 5, wherein the second wiring includes only a signal line that does not constitute a signal transmission path between the second wiring and the ground potential. The flexible substrate according to claim 5 or 6, wherein in the third region, through holes corresponding to the first wiring and the second wiring are respectively formed in one row.

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