Semiconductor device

Abstract

To provide a semiconductor device which includes a substrate and enables the warpage thereof to be reduced.SOLUTION: A semiconductor device comprises: a substrate; a light receiving element; a switching element; and a light emitting element. The substrate includes resin base material and first to third metal pads on the first surface of the resin base material. The light receiving element comprises: a rear surface which is connected to the first and second metal pads and to a portion of the first surface between the first and second metal pads via a first connection member; and first and second bonding pads which are provided on the surface on the opposite side to the rear surface. Each of the first and second bonding pads is provided at positions overlapping any of the first and second metal pads in the direction vertical to the first surface. The switching element is connected to the third metal pad via the second connection member, and is electrically connected to the first and second bonding pads of the light receiving element. The light emitting element is provided on the surface of the light receiving element via a third connection member.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments relate to semiconductor devices.

Background Art

[0002] Semiconductor devices are required to be miniaturized. For example, in a semiconductor device having a structure in which a plurality of semiconductor elements are mounted on a substrate and then the plurality of semiconductor elements are resin-sealed on the substrate, it is desirable to make the substrate thinner and lower-profile. However, when the substrate is made thinner, problems such as warping during heating occur.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments provide a semiconductor device capable of reducing warping of a substrate.

Means for Solving the Problems

[0005] The semiconductor device according to the embodiment includes a substrate, a light receiving element, a switching element, a first conductive member, a second conductive member, and a light emitting element. The substrate has a resin base material and first to third metal pads. The first to third metal pads are arranged on a first surface of the resin base material, and the third metal pad is spaced apart from the first metal pad and the second metal pad. The light receiving element is provided on the first surface side of the resin base material, and has a back surface connected via a first connection member to the first metal pad, the second metal pad, and a part of the first surface between the first metal pad and the second metal pad, and a front surface opposite to the back surface, and further has first and second bonding pads provided on the front surface. The first and second bonding pads are provided at positions overlapping either the first metal pad or the second metal pad in a direction perpendicular to the first surface. The switching element is provided on the first surface side of the resin base material, and has a back surface side electrode connected to the third metal pad via a second connection member, a front surface side electrode provided on a front surface opposite to the back surface on which the back surface side electrode is provided, and a control pad arranged in parallel with the front surface side electrode on the front surface of the switching element. The first conductive member is connected to the front surface side electrode of the switching element and the first bonding pad of the light receiving element, and electrically connects the front surface side electrode and the first bonding pad. The second conductive member is connected to the control pad of the switching element and the second bonding pad of the light receiving element, and electrically connects the control pad and the second bonding pad. The light emitting element is provided on the front surface of the light receiving element via a third connection member, and the third connection member transmits light radiated from the light emitting element toward the light receiving element.

Brief Description of the Drawings

[0006]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0007] Hereinafter, embodiments will be described with reference to the drawings. The same parts in the drawings are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate, and different parts will be described. Note that the drawings are schematic or conceptual, and the relationships between the thickness and width of each part, the ratio of the sizes between parts, etc. are not necessarily the same as those in reality. Also, even when representing the same part, the dimensions and ratios may be represented differently depending on the drawings.

[0008] Furthermore, the arrangement and configuration of each part will be described using the X-axis, Y-axis, and Z-axis shown in each figure. The X-axis, Y-axis, and Z-axis are mutually orthogonal and represent the X-direction, Y-direction, and Z-direction, respectively. Also, there are cases where the Z-direction is described as upward and the opposite direction as downward.

[0009] FIG. 1 is a schematic diagram showing a semiconductor device 1 according to an embodiment. The semiconductor device 1 is, for example, a photo relay. The semiconductor device 1 includes a substrate 10, a light receiving element 20, a switching element 30, and a light emitting element 40.

[0010] The substrate 10 includes a resin base material 11, a plurality of metal pads 13, 15, and 17, an input side terminal 50, and an output side terminal 60. The resin base material 11 is, for example, a sheet-like polyimide.

[0011] The resin base material 11 has a first surface 11F and a second surface 11B opposite to the first surface 11F. A plurality of metal pads 13, 15, and 17 are provided on the first surface 11F. The input-side terminal 50 and the output-side terminal 60 are provided on the second surface 11B of the resin base material 11.

[0012] The plurality of metal pads 13, 15, and 17 are provided spaced apart from each other on the first surface 11F. Also, the input-side terminal 50 and the output-side terminal 60 are provided spaced apart from each other on the second surface 11B. The plurality of metal pads 13, 15, 17, the input-side terminal 50, and the output-side terminal 60 are, for example, copper foils with gold plating on the surface.

[0013] The light-receiving element 20, the switching element 30, and the light-emitting element 40 are provided on the first surface 11F side of the resin base material 11.

[0014] The light-receiving element 20 has a back surface 20BS connected to the metal pad 13 via a first connection member CM1, and a front surface 20FS opposite to the back surface 20BS. The light-receiving element 20 further has a first bonding pad 21 and a second bonding pad 23 provided on the front surface 20FS. The first connection member CM1 is, for example, an adhesive containing resin. The first connection member CM1 may have conductivity or may be insulating.

[0015] The switching element 30 has a back surface-side electrode 31 connected to the metal pad 15 via a second connection member CM2, a front surface-side electrode 33 provided on a front surface opposite to the back surface on which the back surface-side electrode 31 is provided, and a control pad 35 provided on the same front surface as the front surface-side electrode 33. The second connection member CM2 is, for example, a conductive adhesive such as silver paste.

[0016] The front surface-side electrode 33 is electrically connected to the first bonding pad 21 of the light-receiving element 20 via a first conductive member MW1. The control pad 35 is electrically connected to the second bonding pad 23 of the light-receiving element 20 via a second conductive member MW2. The first conductive member MW1 and the second conductive member MW2 are, for example, metal wires.

[0017] The light-emitting element 40 is connected to the surface 20FS of the light-receiving element 20 via a third connection member CM3. The third connection member CM3 is, for example, a transparent resin and transmits light radiated from the light-emitting element 40 toward the light-receiving element 20. The light-emitting element 40 is electrically connected to the metal pad 17 by a third conductive member MW3. The third conductive member MW3 is, for example, a metal wire.

[0018] The light-emitting element 40 is sealed on the surface 20FS of the light-receiving element 20 by a resin member 70. The resin member 70 is, for example, silicone. Further, the light-receiving element 20, the switching element 30, and the resin member 70 are sealed on the first surface 11F side of the resin base material 11 by a resin member 80. The resin member 80 is, for example, an epoxy resin or a silicone resin.

[0019] Figs. 2(a) and (b) are other schematic views showing the semiconductor device 1 according to the embodiment. Fig. 2(a) is a perspective view showing the semiconductor device 1. Fig. 2(b) is a plan view showing the configuration on the first surface 11F of the resin base material 11. In Fig. 2(b), the resin members 70 and 80 are omitted.

[0020] As shown in Fig. 2(a), the semiconductor device 1 includes, for example, a first switching element 30a and a second switching element 30b. The first switching element 30a and the second switching element 30b are each electrically connected to the light-receiving element 20.

[0021] In addition to the light-receiving element 20, the switching element 30, and the light-emitting element 40, the resin member 80 also seals the metal pads 13, 15, 17 and the conductive member MW provided on the first surface 11F of the resin base material 11 inside. In other words, the components provided on the substrate 10 are accommodated inside a resin package formed by the resin base material 11 and the resin member 80. In the following description, the first switching element 30a and the second switching element 30b may be described as the switching element 30 without distinction. The same applies to other components.

[0022] As shown in FIG. 2(b), the plurality of metal pads 13, 15, and 17 include a first metal pad 13a, a second metal pad 13b, a third metal pad 15a, a fourth metal pad 15b, a fifth metal pad 17a, and a sixth metal pad 17b.

[0023] The first metal pad 13a, the third metal pad 15a, and the fifth metal pad 17a are arranged in a direction along the first surface 11F, for example, in the X direction. The first metal pad 13a is provided between the third metal pad 15a and the fifth metal pad 17a.

[0024] The second metal pad 13b, the fourth metal pad 15b, and the sixth metal pad 17b are arranged, for example, in the X direction. The second metal pad 13b is provided between the fourth metal pad 15b and the sixth metal pad 17b.

[0025] The first metal pad 13a and the second metal pad 13b are spaced apart from each other and arranged in a direction intersecting the X direction, for example, in the Y direction. The third metal pad 15a and the fourth metal pad 15b are also spaced apart from each other and arranged, for example, in the Y direction. Also, the fifth metal pad 17a and the sixth metal pad 17b are spaced apart from each other and arranged, for example, in the Y direction.

[0026] The light receiving element 20 is provided across the first metal pad 13a and the second metal pad 13b. The light receiving element 20 is connected to the first metal pad 13a, the second metal pad 13b, and a part of the first surface 11F between the first metal pad 13a and the second metal pad 13b via the first connection member CM1. Also, the light receiving element 20 has first bonding pads 21a and 21b and second bonding pads 23a and 23b. The first bonding pad 21a and the second bonding pad 23a are provided at positions overlapping the first metal pad 13a in a direction perpendicular to the first surface 11F of the resin base material 11, for example, in the Z direction. The first bonding pad 21b and the second bonding pad 23b are provided at positions overlapping the second metal pad 13b, for example, in the Z direction.

[0027] The first switching element 30a is provided on the third metal pad 15a via the second connection member CM2. The first switching element 30a has a back surface side electrode 31 (see FIG. 1), a front surface side electrode 33a, and a control pad 35a. The back surface side electrode 31 is connected to the third metal pad 15a via the second connection member CM2. The second connection member CM2 has conductivity, and the back surface side electrode 31 is electrically connected to the third metal pad 15a. The front surface side electrode 33a is electrically connected to the first bonding pad 21a of the light receiving element 20 via the first conductive member MW1. The first conductive member MW1 is, for example, a metal wire and is connected to the front surface side electrode 33a and the first bonding pad 21a. The control pad 35a is electrically connected to the second bonding pad 23a of the light receiving element 20 via the second conductive member MW2. The second conductive member MW2 is, for example, a metal wire and is connected to the control pad 35a and the second bonding pad 23a.

[0028] The second switching element 30b is provided on the fourth metal pad 15b via another second connection member CM2. The second switching element 30b has another back surface side electrode 31, a front surface side electrode 33b, and a control pad 35b. The back surface side electrode 31 is electrically connected to the fourth metal pad 15b via the second connection member CM2. The front surface side electrode 33b is electrically connected to the first bonding pad 21b of the light receiving element 20 via the fourth conductive member MW4. The control pad 35b is electrically connected to the second bonding pad 23b of the light receiving element 20 via the fifth conductive member MW5. The fourth conductive member MW4 and the fifth conductive member MW5 are, for example, metal wires.

[0029] Also, the front surface side electrode 33a of the first switching element 30a is electrically connected to the front surface side electrode 33b of the second switching element 30b via the sixth conductive member MW6. The front surface side electrode 33a may be electrically connected to the front surface side electrode 33b via a plurality of sixth conductive members MW6. The sixth conductive member MW6 is, for example, a metal wire.

[0030] The light-emitting element 40 is provided on the surface 20FS of the light-receiving element 20 (see FIG. 1) via the third connection member CM3. The light-emitting element 40 is provided between the first bonding pads 21a and 21b and between the second bonding pads 23a and 23b.

[0031] The light-emitting element 40 has a back surface connected to the light-receiving element 20 via the third connection member CM3 and a surface opposite to the back surface. The light-emitting element 40 has a first electrode 41 and a second electrode 43. The first electrode 41 and the second electrode 43 are arranged on the surface opposite to the back surface. The first electrode 41 is electrically connected to the fifth metal pad 17a via the third conductive member MW3. The second electrode 43 is electrically connected to the sixth metal pad 17b via the seventh conductive member MW7. The seventh conductive member MW7 is, for example, a metal wire.

[0032] FIGS. 3(a) to 3(c) are schematic views showing the substrate 10 of the semiconductor device 1 according to the embodiment. FIG. 3(a) is a plan view showing the second surface 11B of the resin base material 11. FIG. 3(b) is a cross-sectional view taken along the line A-A shown in FIG. 3(a). FIG. 3(c) is a cross-sectional view taken along the line B-B shown in FIG. 3(a).

[0033] As shown in FIG. 3(a), the semiconductor device 1 includes a plurality of input-side terminals 50 and a plurality of output-side terminals 60. The plurality of input-side terminals 50 and the plurality of output-side terminals 60 are provided so as to be separated from each other. The input-side terminals 50 and the output-side terminals 60 are, for example, copper foils plated with gold.

[0034] The plurality of input-side terminals 50 and the plurality of output-side terminals 60 include, for example, a first input-side terminal 50a, a second input-side terminal 50b, a first output-side terminal 60a, and a second output-side terminal 60b. The first input-side terminal 50a and the second input-side terminal 50b are arranged, for example, in the Y direction on the second surface 11B of the resin base material 11. The first output-side terminal 60a and the second output-side terminal 60b are arranged, for example, in the Y direction on the second surface 11B of the resin base material 11. Further, the first input-side terminal 50a and the first output-side terminal 60a are arranged, for example, in the X direction. The second input-side terminal 50b and the second output-side terminal 60b are arranged, for example, in the X direction.

[0035] As shown in FIG. 3(b), the resin base material 11 extends between the first input-side terminal 50a and the fifth metal pad 17a. Further, the resin base material 11 extends between the first output-side terminal 60a and the third metal pad 15a. The first input-side terminal 50a is electrically connected to the fifth metal pad 17a via a via contact BC1 provided in the resin base material 11. The first output-side terminal 60a is electrically connected to the third metal pad 15a via a via contact BC2 provided in the resin base material 11. Further, the first output-side terminal 60a may be electrically connected to the third metal pad 15a via a plurality of via contacts BC2.

[0036] The first metal pad 13a is provided on the side opposite to a part of the second surface 11B of the resin base material 11 located between the first input-side terminal 50a and the first output-side terminal 60a. The first metal pad 13a is provided so as to overlap, for example, a part of the first input-side terminal 50a and a part of the first output-side terminal 60a through a part of the resin base material 11 in the Z direction.

[0037] As shown in FIG. 3(c), the resin base material 11 extends between the second input side terminal 50b and the sixth metal pad 17b. Further, the resin base material 11 extends between the second output side terminal 60b and the fourth metal pad 15b. The second input side terminal 50b is electrically connected to the sixth metal pad 17b via a via contact BC3 provided in the resin base material 11. The second output side terminal 60b is electrically connected to the fourth metal pad 15b via a via contact BC4 provided in the resin base material 11. Further, the second output side terminal 60b may be electrically connected to the fourth metal pad 15b via a plurality of via contacts BC4.

[0038] The second metal pad 13b is provided on the opposite side of a part of the second surface 11B of the resin base material 11 located between the second input side terminal 50b and the second output side terminal 60b. The second metal pad 13b is provided so as to overlap a part of the second input side terminal 50b and a part of the second output side terminal 60b via another part of the resin base material 11 in the Z direction, for example.

[0039] FIG. 4 is a circuit diagram showing the semiconductor device 1 according to the embodiment. The light receiving element 20 is, for example, a photodiode. The first switching element 30a and the second switching element 30b are, for example, MOS transistors. The light emitting element 40 is, for example, a light emitting diode.

[0040] The light receiving element 20 includes a plurality of photodiodes 25 and a control circuit 27. The plurality of photodiodes 25 are connected in series. The photodiode 25 is configured to detect the light of the light emitting element 40. The control circuit 27 is, for example, a waveform shaping circuit. Further, the control circuit 27 may be a discharge circuit, a protection circuit, or the like.

[0041] The output of the photodiode 25 is output to the first bonding pads 21a, 21b, the second bonding pads 23a and 23b via the control circuit 27. The first bonding pads 21a and 21b are electrically connected to, for example, the cathode side of the photodiode 25. The second bonding pads 23a and 23b are electrically connected to, for example, the anode side of the photodiode 25.

[0042] The first bonding pad 21a of the light receiving element 20 is electrically connected to the source S (surface side electrode 33a) of the switching element 30a via the first conductive member MW1. Also, the first bonding pad 21b of the light receiving element 20 is electrically connected to the source S (surface side electrode 33b) of the switching element 30b via the fourth conductive member MW4. The source S of the switching element 30a is connected to the source S of the switching element 30b via the sixth conductive member MW6.

[0043] The second bonding pad 23a of the light receiving element 20 is electrically connected to the gate G (control pad 35a) of the first switching element 30a via the second conductive member MW2. The second bonding pad 23b of the light receiving element 20 is electrically connected to the gate G (control pad 35b) of the second switching element 30b via the fifth conductive member MW5.

[0044] The light emitting element 40 is electrically connected to the first input side terminal 50a via the third conductive member MW3. The first input side terminal 50a is electrically connected to the fifth metal pad 17a via the via contact BC1 (see Fig. 3(b)), and the third conductive member MW3 is bonded to the fifth metal pad 17a and the first electrode 41 of the light emitting element 40 (see Fig. 2(b)). The first electrode 41 is electrically connected to, for example, the cathode of the light emitting diode.

[0045] Further, the light-emitting element 40 is electrically connected to the second input-side terminal 50b via the seventh conductive member MW7. The second input-side terminal 50b is electrically connected to the sixth metal pad 17b via the via contact BC3 (see Fig. 3(b)), and the seventh conductive member MW7 is bonded to the sixth metal pad 17b and the second electrode 43 of the light-emitting element 40. The second electrode 43 is electrically connected to, for example, the anode of the light-emitting diode.

[0046] The first output-side terminal 60a is electrically connected to the drain D (back-side electrode 31) of the first switching element 30a. The first output-side terminal 60a is electrically connected to the third metal pad 15a via the via contact BC2 (see Fig. 3(a)), and the back-side electrode 31 of the first switching element 30a is electrically connected to the third metal pad 15a via the second connection member CM2 (see Fig. 2(b)).

[0047] The second output-side terminal 60b is electrically connected to the drain D (another back-side electrode 31) of the second switching element 30b. The second output-side terminal 60b is electrically connected to the fourth metal pad 15b via the via contact BC4 (see Fig. 3(b)), and the back-side electrode 31 of the second switching element 30b is electrically connected to the fourth metal pad 15b via another second connection member CM2 (see Fig. 2(b)).

[0048] For example, a signal for controlling on / off the electrical conduction between the first output-side terminal 60a and the second output-side terminal 60b is input to the first input-side terminal 50a and the second input-side terminal 50b. The light-emitting element 40 emits an optical signal corresponding to the signal input to the first input-side terminal 50a and the second input-side terminal 50b, and the light-receiving element 20 detects the optical signal emitted from the light-emitting element 40. The light-receiving element 20 outputs a control signal corresponding to the optical signal to the gates G of the first switching element 30a and the second switching element 30b. Thereby, the electrical conduction between the first output-side terminal 60a and the second output-side terminal 60b is controlled.

[0049] For example, when passing a high-frequency signal from the first output terminal 60a to the second output terminal 60b, it is preferable to reduce the impedance between the first output terminal 60a and the second output terminal 60b and reduce the transmission loss. In the semiconductor device 1, by reducing the thickness of the resin substrate 11 in the Z direction, the impedance between the switching element 30a and the first output terminal 60a and between the switching element 30b and the second output terminal 60b is reduced. Thereby, the passing characteristics of the high-frequency signal between the first output terminal 60a and the second output terminal 60b can be improved.

[0050] The thickness of the resin substrate 11 in the Z direction is, for example, 50 micrometers. The thickness of each of the metal pads 13, 15, and 17 in the Z direction is, for example, 30 micrometers, and the thickness of each of the input terminal 50 and the output terminal 60 in the Z direction is also, for example, 30 micrometers. Thus, it is preferable that the thickness of the resin substrate 11 in the Z direction is thinner than the combined thickness of the copper foils provided on the first surface 11F and the second surface 11B, respectively. However, when such a thin resin substrate 11 is used for the substrate 10, for example, thermal stress caused by the difference between the linear thermal expansion coefficient of the copper foil and the linear thermal expansion coefficient of the resin substrate 11 causes warping or deformation of the resin substrate 11. Therefore, in the manufacturing process of the semiconductor device 1, problems associated with deterioration of the flatness of the resin substrate 11 occur.

[0051] As shown in FIGS. 3(b) and 3(c), the input terminal 50 faces the metal pad 17 through the resin substrate 11. Also, the output terminal 60 faces the metal pad 15 through the resin substrate 11. Therefore, the thermal stress caused by the difference between the linear thermal expansion coefficients of the two and the linear thermal expansion coefficient of the resin substrate 11 is canceled out and reduced. However, on the second surface 11B side of the resin substrate 11 facing the metal pad 13, no copper foil is provided, and the thermal stress is not canceled out. For this reason, in the substrate 10, warping and deformation caused by the metal pad 13 are likely to occur.

[0052] On the other hand, in the semiconductor device 1, by providing a plurality of metal pads 13 on the resin base material 11, the respective occupied areas are reduced, and the thermal stress is reduced. Further, by connecting a part of the first surface 11F of the resin base material 11 located between the plurality of metal pads 13 and the light receiving element 20 via the first connection member CM1, the connection strength between the substrate 10 and the light receiving element 20 can be improved. That is, by adding the bonding of resin to the bonding of resin and metal between the substrate 10 and the first connection member CM1, it becomes possible to improve the connection strength.

[0053] Furthermore, the first bonding pad 21 and the second bonding pad 23 of the light receiving element 20 are provided at positions overlapping the metal pads 13 in the Z direction, respectively. Thereby, the absorption of ultrasonic waves by the resin base material 11 generated when the conductive member MW is ultrasonically bonded onto the bonding pads 21 and 23 can be suppressed, and the bonding strength of the conductive member MW can be improved.

[0054] Also, as shown in FIGS. 3(a) to 3(c), a part of the metal pad 13 is arranged so as to overlap the input side terminal 50 or the output side terminal 60. Thereby, the absorption or dissipation of ultrasonic waves by the resin base material 11 can be further reduced. Also, the metal pad 13 may be arranged so as to overlap the input side terminal 50 and the output side terminal 60.

[0055] FIGS. 5(a) and 5(b) are schematic plan views showing the substrate 10 of the semiconductor device 1 according to the embodiment. FIG. 5(a) is a plan view showing the first surface 11F of the resin base material 11. FIG. 5(b) is a plan view showing the first surface 11F of another substrate 10. The broken lines in the figure represent the positions of the light receiving element 20 and the light emitting element 40.

[0056] As shown in FIG. 5(a), the light receiving element 20 is provided straddling the first metal pad 13a and the second metal pad 13b. Also, the light emitting element 40 is provided at a position straddling the first metal pad 13a and the second metal pad 13b on the light receiving element 20.

[0057] The distance between the first metal pad 13a and the second metal pad 13b is substantially the same as the distance between the third metal pad 15a and the fourth metal pad 15b. The embodiment is not limited to this example. For example, the distance between the first metal pad 13a and the second metal pad 13b may be wider than the distance between the third metal pad 15a and the fourth metal pad 15b. Also, the space between the first metal pad 13a and the second metal pad 13b may be equally spaced as shown in Fig. 5(a), or the central distance and the end distance in the X direction may be different.

[0058] As shown in Fig. 5(b), the first metal pad 13a may be provided to be connected to the second metal pad 13b via the metal connection part 13c. A part of the first surface 11F of the resin base material 11 is surrounded by the first metal pad 13a, the second metal pad 13b, and the two metal connection parts 13c.

[0059] The metal connection part 13c is provided on the first surface 11F of the resin base material 11 so as to connect the outer edge of the first metal pad 13a facing the third metal pad 15a and the outer edge of the second metal pad 13b facing the fourth metal pad 15b.

[0060] Another metal connection part 13c is provided so as to connect the outer edge of the first metal pad 13a facing the fifth metal pad 17a and the outer edge of the second metal pad 13b facing the sixth metal pad 17b.

[0061] For example, for the first connection member CM1 that connects the substrate 10 and the light receiving element 20, it is preferable to use a conductive adhesive such as silver paste with a large adhesive force to metal. However, after the first connection member CM1 is applied on the first surface 11F of the resin base material 11, it may spread outward from the space between the metal pads 13. For this reason, the distance between the first connection member CM1 and the metal pad 15 becomes narrow, and the dielectric breakdown voltage between the metal pad 13 and the metal pad 15 may decrease. In this example, by providing the metal connection part 13c, it is possible to prevent the first connection member CM1 from spreading outside the space between the metal pads 13. Thereby, a decrease in the dielectric breakdown voltage between the metal pad 13 and the metal pad 15 can be avoided.

[0062] FIGS. 6(a) and 6(b) are schematic plan views showing a substrate 10 of a semiconductor device 1 according to a modified example of an embodiment. FIGS. 6(a) and 6(b) are plan views showing a first surface 11F of a resin base material 11. The dashed lines in the figure represent the positions of the light receiving element 20 and the light emitting element 40.

[0063] In the example shown in FIG. 6(a), the substrate 10 further includes a seventh metal pad 13d and an eighth metal pad 13e. The seventh metal pad 13d and the eighth metal pad 13e are provided on the first surface 11F of the resin base material 11.

[0064] The seventh metal pad 13d is provided between the first metal pad 13a and the fifth metal pad 17a. The seventh metal pad 13d is provided spaced apart from the first metal pad 13a and the fifth metal pad 17a.

[0065] The eighth metal pad 13e is provided between the second metal pad 13b and the sixth metal pad 17b. The eighth metal pad 13e is provided spaced apart from the second metal pad 13b and the sixth metal pad 17b. Further, the seventh metal pad 13d and the eighth metal pad 13e are arranged in the Y direction and are provided spaced apart from each other.

[0066] Note that the intervals between the respective metal pads may be the same or different. Also, the spaces between the respective metal pads may have a constant width or may not have a constant width.

[0067] In this way, by arranging the four metal pads 13 with reduced occupied areas respectively, the thermal stress applied to the resin base material 11 can be reduced. Also, a part of the area of the first surface 11F of the resin base material 11 located between adjacent metal pads 13 can be widened, and the connection strength of the light receiving element 20 to the substrate 10 can be increased.

[0068] In the Z direction perpendicular to the first surface 11F of the resin substrate 11, the first bonding pad 21a of the light receiving element 20 is provided so as to overlap the first metal pad 13a, and the second bonding pad 23a is provided so as to overlap the seventh metal pad 13d. Further, the first bonding pad 21b of the light receiving element 20 is provided so as to overlap the second metal pad 13b. The second bonding pad 23b is provided so as to overlap the eighth metal pad 13e.

[0069] In the example shown in FIG. 6(b), metal connection portions 13c, 13f, 13g, and 13h are further provided. The metal connection portions 13c, 13f, 13g, and 13h are provided on the first surface 11F of the resin substrate 11 so as to surround a part of the first surface 11F located between the first metal pad 13a and the second metal pad 13b, between the first metal pad 13a and the seventh metal pad 13d, between the second metal pad 13b and the eighth metal pad 13e, and between the seventh metal pad 13d and the eighth metal pad 13e.

[0070] The metal connection portion 13c is provided so as to connect the outer edge of the first metal pad 13a facing the third metal pad 15a and the outer edge of the second metal pad 13b facing the fourth metal pad 15b.

[0071] The metal connection portion 13f is provided so as to connect the outer edge of the seventh metal pad 13d facing the fifth metal pad 17a and the outer edge of the eighth metal pad 13e facing the sixth metal pad 17b. The metal connection portion 13g is provided so as to connect the outer edge of the first metal pad 13a along the X direction and the outer edge of the seventh metal pad 13d along the X direction. Further, the metal connection portion 13h is provided so as to connect the outer edge of the second metal pad 13b along the X direction and the outer edge of the eighth metal pad 13e along the X direction. Thereby, the metal connection portions 13c, 13f, 13g, and 13h suppress the first connection member CM1 from spreading outward from the space between the plurality of metal pads 13.

[0072] Figs. 7(a) and (b) are schematic plan views showing a substrate 10 of a semiconductor device 1 according to another modification of the embodiment. Figs. 7(a) and (b) are plan views showing a first surface 11F of a resin base material 11. The broken lines in the figures represent the positions of the light receiving element 20 and the light emitting element 40.

[0073] As shown in Fig. 7(a), the second metal pad 13b is spaced apart from the first metal pad 13a and is provided so as to surround the first metal pad 13a. The first metal pad 13a is, for example, circular.

[0074] The light emitting element 40 is provided at a position overlapping the first metal pad 13a in the Z direction. The first bonding pads 21a, 21b and the second bonding pads 23a, 23b of the light receiving element 20 are provided at positions overlapping the second metal pad 13b in the Z direction.

[0075] Also in the example shown in Fig. 7(b), the second metal pad 13b is spaced apart from the first metal pad 13a and is provided so as to surround the first metal pad 13a. The first metal pad 13a is, for example, triangular. The light emitting element 40 is provided at a position overlapping the first metal pad 13a in the Z direction. The first bonding pads 21a, 21b and the second bonding pads 23a, 23b of the light receiving element 20 are provided at positions overlapping the second metal pad 13b in the Z direction.

[0076] Also in these examples, the light receiving element 20 is provided straddling the first metal pad 13a and the second metal pad 13b. By widening a part of the area of the first surface 11F of the resin base material 11 located between the first metal pad 13a and the second metal pad 13b, the occupied areas of the first metal pad 13a and the second metal pad 13b can be reduced, and the thermal stress in the resin base material 11 can be reduced. Thereby, warping or deformation of the resin base material 11 can be suppressed. Also, the connection strength of the light receiving element 20 to the substrate 10 can be increased. Note that the shape of the first metal pad 13a surrounded by the second metal pad 13b is not limited to the above example, and may be, for example, polygonal.

[0077] FIG. 8 is a graph showing the characteristics of the semiconductor device 1 according to the embodiment. The horizontal axis is the frequency of the signal propagating between the first output terminal 60a and the second output terminal 60b. The vertical axis is the insertion loss between the first output terminal 60a and the second output terminal 60b.

[0078] "EB" shown in FIG. 8 represents the characteristics of the semiconductor device 1. Also, "CE" represents the characteristics of the semiconductor device according to the comparative example. In the semiconductor device according to the comparative example, the first metal pad 13a and the second metal pad 13b (see FIG. 5(a)) are provided integrally.

[0079] As shown in FIG. 8, the frequency band of the semiconductor device 1 is wider than that of the semiconductor device according to the comparative example. That is, by separating the metal pad 13 on which the light receiving element 20 is mounted into the first metal pad 13a and the second metal pad 13b, the frequency characteristics can be improved.

[0080] Due to the high speed of semiconductor devices such as memory elements in recent years, for example, the high speed of the photorelay used in its tester has also become an urgent issue. As shown in FIG. 8, in the semiconductor device 1 according to the embodiment, high-frequency characteristics up to the 30 GHz band are realized by reducing the overall size and thinning the substrate 10. Further, by arranging the plurality of metal pads on which the light receiving element 20 is mounted so as to be separated from each other, it can be seen that the bandwidth (-3 dB) of the signal path propagating from the first output terminal 60a to the second output terminal 60b, or vice versa, can be widened from 25 GHz to 30 GHz. Such an effect is considered to be because the parasitic capacitance in parallel with the signal path between the first output terminal 60a and the second output terminal 60b is significantly reduced by the division of the mount pads.

[0081] Although some embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

[0082] (Appendix 1) A substrate having a resin base material and first to third metal pads, wherein the first to third metal pads are arranged on a first surface of the resin base material, and the third metal pad is separated from the first metal pad and the second metal pad, the substrate A light receiving element provided on the first surface side of the resin base material, having a back surface connected via a first connecting member to a part of the first surface between the first metal pad, the second metal pad, and the first metal pad and the second metal pad, and a surface opposite to the back surface, and further having first and second bonding pads provided on the surface, wherein the first and second bonding pads are provided at positions overlapping either the first metal pad or the second metal pad in a direction perpendicular to the first surface, the light receiving element A switching element provided on the first surface side of the resin base material, having a back surface side electrode connected to the third metal pad via a second connecting member, a surface side electrode provided on a surface opposite to the back surface on which the back surface side electrode is provided, and a control pad arranged side by side with the surface side electrode on the surface of the switching element, the switching element A first conductive member connected to the surface side electrode of the switching element and the first bonding pad of the light receiving element, and electrically connecting the surface side electrode and the first bonding pad A second conductive member connected to the control pad of the switching element and the second bonding pad of the light receiving element, and electrically connecting the control pad and the second bonding pad A light-emitting element provided on the surface of the light-receiving element via a third connection member, wherein the third connection member transmits light radiated from the light-emitting element toward the light-receiving element, and the light-emitting element. A semiconductor device including the same.

[0083] (Appendix 2) The semiconductor device according to Appendix 1, wherein the second metal pad is provided so as to be separated from the first metal pad.

[0084] (Appendix 3) The semiconductor device according to Appendix 1, wherein the substrate is provided on the first surface of the resin base material and further has a metal connection portion connecting the first metal pad and the second metal pad, and the first metal pad, the second metal pad, and the metal connection portion surround the part of the first surface.

[0085] (Appendix 4) The semiconductor device further includes another switching element provided on the first surface side of the resin base material and electrically connected to the light-receiving element. The substrate further includes a fourth metal pad provided on the first surface of the resin base material. The fourth metal pad is provided so as to be separated from the first to third metal pads. The third metal pad and the fourth metal pad are arranged in the same direction as the direction in which the first metal pad and the second metal pad are arranged on the first surface. The semiconductor device according to any one of Appendices 1 to 3, wherein the another switching element is connected to the fourth metal pad via another second connection member.

[0086] (Appendix 5) The substrate further includes fifth and sixth metal pads provided on the first surface. The fifth and sixth metal pads are arranged in the same direction as the direction in which the first and second metal pads are arranged on the first surface. The first metal pad is located between the third metal pad and the fifth metal pad. The second metal pad is located between the third metal pad and the sixth metal pad, A part of the first surface extends between the first metal pad and the second metal pad, between the first metal pad and the fifth metal pad, between the second metal pad and the sixth metal pad, and between the fifth metal pad and the sixth metal pad, The light receiving element has a back surface connected to the first metal pad, the second metal pad, the fifth metal pad, the sixth metal pad, and a part of the first surface via the first connecting member, The first and second bonding pads of the light receiving element are provided at positions overlapping any one of the first metal pad, the second metal pad, the fifth metal pad, and the sixth metal pad in a direction perpendicular to the first surface. The semiconductor device according to Supplementary Note 1.

[0087] (Supplementary Note 6) The first metal pad, the second metal pad, the fifth metal pad, and the sixth metal pad are provided separately from each other. The semiconductor device according to Supplementary Note 5.

[0088] (Supplementary Note 7) The substrate further includes metal connection portions provided between the first metal pad and the second metal pad, between the second metal pad and the sixth metal pad, between the fifth metal pad and the sixth metal pad, and between the fifth metal pad and the first metal pad, and arranged so as to surround the part of the first surface. The semiconductor device according to Supplementary Note 5.

[0089] (Supplementary Note 8) The second metal pad is separated from the first metal pad and surrounds the first metal pad. The semiconductor device according to Supplementary Note 1.

[0090] (Supplementary Note 9) The light emitting element is provided at a position overlapping the first metal pad in the direction perpendicular to the first surface of the resin base material. The semiconductor device according to Supplementary Note 8.

[0091] (Supplementary Note 10) The semiconductor device according to supplementary note 9, wherein the first bonding pad and the second bonding pad of the light receiving element are provided at positions overlapping the second metal pad in the direction perpendicular to the first surface of the substrate.

[0092] (Supplementary note 11) The substrate has an input side terminal and an output side terminal provided on a second surface opposite to the first surface of the resin base material, The semiconductor device according to any one of supplementary notes 1 to 10, wherein the input side terminal is electrically connected to the light emitting element, and the output side terminal is electrically connected to the switching element via the third metal pad and the second connection member.

Explanation of reference numerals

[0093] 1…Semiconductor device, 10…Substrate, 11…Resin base material, 11B…Second surface, 11F…First surface, 13, 15, 17…Metal pads, 13a…First metal pad, 13b…Second metal pad, 13c, 13f, 13g, 13h…Metal connection parts, 13d…Seventh metal pad, 13e…Eighth metal pad, 15a…Third metal pad, 15b…Fourth metal pad, 17a…Fifth metal pad, 17b…Sixth metal pad, 20…Light-receiving element, 20BS…Back surface, 20FS…Front surface, 21, 23…Bonding pads, 21a, 21b…First bonding pads, 23a, 23b…Second bonding pads, 25…Photodiode, 27…Control circuit, 30…Switching element, 30a…First switching element, 30b…Second switching element, 31…Back surface side electrode, 33, 33a, 33b…Front surface side electrodes, 35, 35a, 35b…Control pads, 40…Light-emitting element, 41…First electrode, 43…Second electrode, 50…Input side terminal, 50a…First input side terminal, 50b…Second input side terminal, 60…Output side terminal, 60a…First output side terminal, 60b…Second output side terminal, 70, 80…Resin members, BC1, BC2, BC3, BC4…Via contacts, CM1…First connection member, CM2…Second connection member, CM3…Third connection member, MW1…First conductive member, MW2…Second conductive member, MW3…Third conductive member, MW4…Fourth conductive member, MW5…Fifth conductive member, MW6…Sixth conductive member, MW7…Seventh conductive member

Claims

1. A substrate having a resin base material and first to third metal pads, wherein the first to third metal pads are arranged on a first surface of the resin base material, and the third metal pad is spaced apart from the first metal pad and the second metal pad, the substrate; A light receiving element provided on the first surface side of the resin base material, having a back surface connected via a first connecting member to a part of the first surface between the first metal pad, the second metal pad, and the first metal pad and the second metal pad, and a front surface opposite to the back surface, and further having first and second bonding pads provided on the front surface, wherein the first and second bonding pads are provided at positions overlapping either the first metal pad or the second metal pad in a direction perpendicular to the first surface, the light receiving element; A switching element provided on the first surface side of the resin base material, having a back surface side electrode connected to the third metal pad via a second connecting member, a front surface side electrode provided on a front surface opposite to the back surface on which the back surface side electrode is provided, and a control pad arranged in parallel with the front surface side electrode on the front surface of the switching element, the switching element; A first conductive member connected to the front surface side electrode of the switching element and the first bonding pad of the light receiving element, and electrically connecting the front surface side electrode and the first bonding pad; A second conductive member connected to the control pad of the switching element and the second bonding pad of the light receiving element, and electrically connecting the control pad and the second bonding pad; A light emitting element provided on the front surface of the light receiving element via a third connecting member, wherein the third connecting member transmits light radiated from the light emitting element toward the light receiving element, the light emitting element; A semiconductor device comprising the above.

2. The semiconductor device according to Claim 1, wherein the second metal pad is provided so as to be spaced apart from the first metal pad.

3. The substrate is provided on the first surface of the resin base material, and further has a metal connection portion connecting the first metal pad and the second metal pad, and the first metal pad, the second metal pad, and the metal connection portion surround the part of the first surface. The semiconductor device according to Claim 1.

4. Further comprising another switching element provided on the first surface side of the resin substrate and electrically connected to the light receiving element. The substrate further includes a fourth metal pad provided on the first surface of the resin substrate. The fourth metal pad is provided separately from the first to third metal pads. The third metal pad and the fourth metal pad are arranged in the same direction as the direction in which the first metal pad and the second metal pad are arranged on the first surface. The semiconductor device according to claim 1, wherein the another switching element is connected on the fourth metal pad via another second connection member.

5. The substrate further includes fifth and sixth metal pads provided on the first surface. The fifth and sixth metal pads are arranged in the same direction as the direction in which the first and second metal pads are arranged on the first surface. The first metal pad is located between the third metal pad and the fifth metal pad. The second metal pad is located between the third metal pad and the sixth metal pad. A part of the first surface extends between the first metal pad and the second metal pad, between the first metal pad and the fifth metal pad, between the second metal pad and the sixth metal pad, and between the fifth metal pad and the sixth metal pad. The light receiving element has a back surface connected to the first metal pad, the second metal pad, the fifth metal pad, the sixth metal pad, and a part of the first surface via the first connection member. The first and second bonding pads of the light receiving element are provided at positions overlapping any one of the first metal pad, the second metal pad, the fifth metal pad, and the sixth metal pad in a direction perpendicular to the first surface, according to the semiconductor device of claim 1.

6. The semiconductor device according to claim 5, wherein the first metal pad, the second metal pad, the fifth metal pad, and the sixth metal pad are provided separately from each other.

7. The semiconductor device according to claim 5, further comprising metal connection portions provided between the first metal pad and the second metal pad, between the second metal pad and the sixth metal pad, between the fifth metal pad and the sixth metal pad, and between the fifth metal pad and the first metal pad, and arranged to surround the part of the first surface.

8. The semiconductor device according to claim 1, wherein the second metal pad is spaced apart from the first metal pad and surrounds the first metal pad.

9. The semiconductor device according to claim 8, wherein the light-emitting element is provided at a position overlapping the first metal pad in the direction perpendicular to the first surface of the resin substrate.

10. The semiconductor device according to claim 9, wherein the first bonding pad and the second bonding pad of the light-receiving element are provided at positions overlapping the second metal pad in the direction perpendicular to the first surface of the substrate.

11. The substrate has an input-side terminal and an output-side terminal provided on a second surface opposite to the first surface of the resin substrate, The semiconductor device according to any one of claims 1 to 10, wherein the input-side terminal is electrically connected to the light-emitting element, and the output-side terminal is electrically connected to the switching element via the third metal pad and the second connection member.

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