JP2015149338A - Semiconductor device, optical scanning device, and image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device capable of easily detecting mounting failures caused by protrusion of conductive paste from the inside of a coating region, in a semiconductor device in which at least two semiconductor chips are adjacent and mounted on a surface of a semiconductor package via the conductive paste.SOLUTION: At three circumferential outsides other than a light receiving element side, of a surface emission laser array 20, a plurality of lead frames 9 are provided depending on the number of light-emission parts of the surface emission laser array 20. Further, wiring 21 is provided between a coating region A of the surface emission laser array 20 and each lead frame 9. The wiring 21 is electrically connected with an abnormality detection terminal 18 provided on a surface emission laser module.

Description

  The present invention relates to a semiconductor device, an optical scanning device, and an image forming apparatus.

  In recent years, image forming apparatuses such as copiers, printers, facsimiles, and multi-functional machines having these functions have increased demands for higher speed, higher density, and higher image quality. In response to these demands, a plurality of scans on the surface to be scanned with a plurality of laser beams emitted from a surface emitting laser having a plurality of light emitting points (vertical cavity surface emitting laser: VCSEL (Vertical Cavity Surface Emitting Laser)) 2. Description of the Related Art Image forming apparatuses having so-called multi-beam writing type optical scanning devices that simultaneously scan lines have been put into practical use.

  A semiconductor laser used for optical writing in an optical scanning device usually needs to be driven by applying automatic power control (APC), and it is therefore necessary to monitor the light emission amount of the semiconductor laser. In an edge emitting semiconductor laser (edge emitting laser), the amount of light can be monitored by receiving light emitted from the end surface opposite to the light emitting end surface. Light is not emitted to the surface opposite to the upper emission surface. For this reason, in the surface emitting laser, the amount of light cannot be monitored in the same manner as the edge emitting laser.

  Therefore, for example, in the optical device (surface emitting laser module) described in Patent Document 1, a light transmitting member having a light transmitting function is disposed at a predetermined angle on the front side of the emitting surface of the surface emitting laser element, and the light emitting member is separated from the emitting surface. A part of the emitted laser light is reflected to the surface emitting laser element side by the light transmitting member, and the amount of light is monitored by receiving the reflected light.

  An optical device (surface emitting laser module) described in Patent Document 1 includes a surface emitting laser element and a light receiving element that are mounted adjacent to each other on the surface of a semiconductor package, and a predetermined front side of the emitting surface side of the surface emitting laser element. It has a window part made of a light transmitting member inclined at an angle, and a part of the laser light emitted from the surface emitting laser element is reflected to the light receiving element side by the window part, and this reflected light is incident on the light receiving element. I try to let them.

  As described above, the surface-emitting laser element and the light-receiving element are mounted on the surface of the semiconductor package adjacent to each other via a conductive paste such as silver paste. Narrow.

  As described above, since the coating region for mounting the surface emitting laser element is narrow, if the conductive paste used for mounting protrudes from the coating region, the protruding conductive paste is applied to the surrounding lead frame or the like. Mounting defects such as contact may occur.

  The causes of the conductive paste protruding from the application region include, for example, variations in the discharge amount of the conductive paste, variations in the discharge position, variations in the mounting position of the surface emitting laser element, and the like. In order to prevent the conductive paste from protruding from the application region, if the discharge amount of the conductive paste is reduced more than necessary, the bonding area becomes small, and the mounted surface emitting laser element is likely to peel off. A malfunction occurs.

  Therefore, the present invention relates to a semiconductor device in which at least two semiconductor chips (surface emitting laser element (surface emitting laser array) and light receiving element) are adjacently mounted on the surface of the semiconductor package via a conductive paste. It is an object of the present invention to provide a semiconductor device capable of easily inspecting a mounting defect due to protrusion of a conductive paste from an application region.

  In order to achieve the above object, a semiconductor device according to the present invention is a semiconductor device in which at least a first semiconductor chip and a second semiconductor chip are mounted adjacent to each other on one surface of a semiconductor package via a conductive paste. A wiring provided on the one surface so as to surround at least a part of a periphery of the application region of the conductive paste, and the wiring is electrically connected to an inspection terminal provided in the semiconductor device. The conductive paste is applied to the application region, and at least the first semiconductor chip is mounted.

  According to the semiconductor device of the present invention, when the conductive paste is applied to the application region and at least the first semiconductor chip is mounted, whether the mounting failure is caused by the protrusion from the application region of the conductive paste by the inspection terminal. It is possible to easily determine (inspect) whether or not.

1 is a schematic cross-sectional view illustrating a configuration of a surface emitting laser module according to Embodiment 1. FIG. 1 is a schematic plan view showing a configuration of a surface emitting laser module according to Embodiment 1. FIG. FIG. 4 is an explanatory diagram of a laser beam output control operation of the surface emitting laser module according to the first embodiment. FIG. 2 is a diagram schematically showing the vicinity of a surface emitting laser element on a package in Embodiment 1, wherein (a) is a diagram showing a normal time when a conductive paste is applied in an application region; FIG. 4 is a diagram showing an abnormal time when the conductive paste protrudes from the application region. FIG. 6 is a schematic plan view showing a configuration of a surface emitting laser module according to Embodiment 2. FIG. 5 is a diagram schematically showing the vicinity of a surface emitting laser array on a package in Embodiment 2, and (a) is a diagram showing a normal time when a conductive paste is applied in an application region; and (b). FIG. 4 is a diagram showing an abnormal time when the conductive paste protrudes from the application region. FIG. 6 is a schematic plan view showing the configuration of a surface emitting laser module according to Embodiment 3. It is the figure which showed typically the surface emitting laser array vicinity on a package in Embodiment 3, (a) is the figure which showed the normal time when the electrically conductive paste is apply | coated in the application | coating area | region, (b) FIG. 4 is a diagram showing an abnormal time when the conductive paste protrudes from the application region. FIG. 6 is a schematic diagram illustrating a configuration of a laser printer as an example of an image forming apparatus including an optical scanning device according to a fourth embodiment. FIG. 6 is a schematic diagram illustrating a configuration of an optical scanning device according to a fourth embodiment.

Hereinafter, the present invention will be described based on the illustrated embodiments.
<Embodiment 1>
FIG. 1 is a schematic sectional view showing a configuration of a surface emitting laser module as an example of a semiconductor device according to Embodiment 1, and FIG. 2 is a schematic plan view showing a configuration of the surface emitting laser module.

(Configuration and operation of surface emitting laser module)
As shown in FIGS. 1 and 2, the surface emitting laser module 1 according to this embodiment includes a first semiconductor chip as a first semiconductor chip on a plane (one surface) in a semiconductor package (hereinafter simply referred to as “package”) 2. A well-known surface-emitting laser element 3 and a light-receiving element 4 as a second semiconductor are adjacently mounted by die bonding via conductive pastes 5 and 6 such as silver paste.

  On the package 2, a cap portion 8 to which a transparent glass plate 7 is attached so as to be positioned in front of the surface emitting laser element 3 and the light receiving element 4 (upper surface side of the surface emitting laser element 3) is integrally connected. The surface emitting laser element 3 and the light receiving element 4 are sealed. The transparent glass plate 7 is fixed in a state where it is inclined at a predetermined angle (for example, about 20 degrees) with respect to the bottom surface 8a of the cap portion 8. FIG. 2 shows a state where the cap portion 8 is removed.

  The surface emitting laser element 3 and the light receiving element 4 are electrically connected to lead frames 9 and 10 respectively provided in the package 2 via bonding wires 11 and 12 such as gold wires.

  As shown in FIG. 2, an inspection wiring (hereinafter simply referred to as “wiring”) 13 is provided between the surface emitting laser element 3 and the lead frame 9 so as to cross between the two. A wiring 14 is also provided outside the periphery of the light receiving element 4 so as to cross between the light receiving element 4 and the lead frame 10.

  As shown in FIG. 2, a conductive paste application region A, which will be described later, is set on the outer periphery of the surface emitting laser element 3, and the surface emitting laser element 3 is made conductive on a plane in the package 2. When mounting with the paste 5, the conductive paste 5 does not protrude from the inside of the application region A if it is normal.

  The laser light L emitted from the light emitting portion on the emission surface of the surface emitting laser element 3 is emitted through the transparent glass plate 7 of the cap portion 8. At this time, since the transparent glass plate 7 is inclined, a part (for example, about 10%) of the emitted total laser light L is reflected by the transparent glass plate 7, and the reflected light is reflected by a photodiode or the like. Light is received by the light receiving element 4.

  When this surface-emitting laser element 3 is applied to a light source of an optical scanning device of an image forming apparatus (for example, a copier or a printer), for example, as shown in FIG. The output monitor signal a is output to the write controller 15.

  The writing control unit 15 detects the beam intensity of the laser light L emitted from the surface emitting laser element 3 based on the output monitor signal a input from the light receiving element 4, and compares the detected beam intensity with a reference value. . Then, the injection current to the surface emitting laser element 3 is controlled so that the output of the laser light L emitted from the surface emitting laser element 3 becomes a predetermined value. Based on this current control, a write signal (current signal) b is output to the surface emitting laser element 3. The value of the write signal b is held until the next detection of the beam intensity, and the beam intensity of the laser light L output from the surface emitting laser element 3 is kept constant.

  Note that a surface-emitting laser array having a plurality of light-emitting portions by arranging the surface-emitting laser elements 3 in an array may be used as a light source of the optical scanning device.

(Inspection of mounting failure due to protrusion of conductive paste 5)
FIG. 4 is a diagram schematically showing the vicinity of the surface emitting laser element 3 on the package 2 in the present embodiment. FIG. 4A shows the conductive paste 5 applied in the application region A. FIG. FIG. 4B is a diagram showing a normal time, and FIG. 4B is a diagram showing an abnormal time when the conductive paste 5 protrudes from the application region A. FIG.

  As shown in FIG. 4, the pad portion on the surface emitting laser element 3 is electrically connected to the light emitting portion terminal 16 from the lead frame 9 on the package 2 connected via the bonding wire 11. The light emitting unit terminal 16 receives a write signal b from the write control unit 15 (see FIG. 3). The bottom surface of the surface emitting laser element 3 is electrically connected to a ground terminal (GND terminal) 17 via the conductive paste 5. The wiring 13 is electrically connected to an abnormality detection terminal (inspection terminal) 18. The light emitting unit terminal 16, the ground terminal 17, and the abnormality detection terminal 18 are provided on the end surface of the surface emitting laser module 1.

  The abnormality detection terminal 18 is electrically connected to an inspection device 19 that determines an electrical state of the abnormality detection terminal 18 (an open state (no load state) or a ground potential state that is not electrically connected). ing. The wiring 13 is provided between the coating area A on the outer periphery of the surface emitting laser element 3 and the lead frame 9 so as to be close to each other in a non-contact state. Thus, the wiring 13 is provided only on the lead frame 9 side of the application region A.

  4A, when the surface emitting laser element 3 is mounted on the plane in the package 2 with the conductive paste 5, the conductive paste 5 protruding from the bottom surface of the surface emitting laser element 3 is obtained. When it does not protrude from the coating area A, that is, when the protruding conductive paste 5 is not in contact with the wiring 13, it is normal.

  Thus, at the normal time shown in FIG. 4A, the abnormality detection terminal 18 is in an open state (no load state). Therefore, when the inspection device 19 detects that the abnormality detection terminal 18 is in an open state, the protruding conductive paste 5 is in the application region A in a normal state (mounting of the surface emitting laser element 3 is in a normal state). For example, “normal” is displayed on the screen of a display device (not shown).

  In the surface-emitting laser module 1 according to this embodiment, the surface-emitting laser element 3 and the light-receiving element 4 are adjacent to each other, so that the coating region A for mounting the surface-emitting laser element 3 with the conductive paste 5 in the package 2 is provided. Is narrow.

  For this reason, as shown in FIG. 4B, when the surface emitting laser element 3 is mounted on the plane in the package 2 with the conductive paste 5, the conductive paste 5 protruding from the bottom surface of the surface emitting laser element 3. However, a mounting failure may occur that protrudes from the coating area A to the lead frame 9 side. In FIG. 4B, the conductive paste 5 protrudes to the wiring 13, but when the amount of protrusion is larger, the protruding conductive paste 5 reaches the lead frame 9.

  In the present embodiment, since the lead frame 9 is located close to the outside of the wiring 13 as described above, the conductive paste 5 protrudes from the coating region A to the lead frame 9 side and protrudes. When 5 is in contact with the wiring 13, it is an abnormal time. When the protruding conductive paste 5 is in contact with the wiring 13, there is a high possibility that the protruding conductive paste 5 is in contact with the lead frame 9, and the surface emitting laser element 3 is in a defective mounting state. .

  At the time of abnormality shown in FIG. 4B (at the time of mounting failure), since the protruding conductive paste 5 is in contact with the wiring 13, the abnormality detection terminal 18 is in the ground (GND) potential state. Therefore, when the inspection device 19 detects that the abnormality detection terminal 18 is in the ground potential state, the abnormal state (surface emitting laser element) in which the conductive paste 5 protrudes from the coating region A to the lead frame 9 side. 3 is determined to be in a defective state), for example, “Mounting failure” is displayed on the screen of a display device (not shown).

  As described above, when the surface emitting laser element 3 is mounted on the plane in the package 2 via the conductive paste 5 adjacent to the light receiving element 4, the surface emitting laser element 3 is interposed between the surface emitting laser element 3 and the lead frame 9. By determining the electrical state (open state or ground potential state) of the abnormality detection terminal 18 that is electrically connected to the provided wiring 13, mounting defects due to protrusion of the conductive paste 5 from the application region A can be prevented. Can be easily inspected.

  In the present embodiment, the inspection wiring 14 is also provided outside the periphery of the light receiving element 4 so as to cross between the light receiving element 4 and the lead frame 10. Therefore, when the light receiving element 4 is mounted via the conductive paste, the electrical state of the abnormality detection terminal (not shown) electrically connected to the wiring 14 is detected, thereby similarly conducting It can be determined whether or not the mounting is defective due to the protrusion from the paste application area.

<Embodiment 2>
FIG. 5 is a schematic plan view illustrating a configuration of a surface emitting laser module as an example of a semiconductor device according to the second embodiment.

  As shown in FIG. 5, in the surface emitting laser module 1 a according to the present embodiment, the surface emitting laser elements 20 are arranged in an array, and the surface emitting laser array 20 having a structure having a plurality of light emitting units is adjacent to the light receiving element 4. Then, it is mounted on a plane in the package 2 via the conductive paste 5. A cap 8 having the transparent glass plate 7 shown in FIG. 1 is provided in front of the surface emitting laser array 20 and the light receiving element 4.

  A plurality of lead frames 9 are provided in the package 2 according to the number of light emitting portions of the surface emitting laser array 20 on the outer periphery of the three sides excluding the light receiving element 4 side of the surface emitting laser array 20. The upper surface of the surface emitting laser array 20 and each lead frame 9 are electrically connected via bonding wires 11 such as gold wires.

  Wiring 21 is provided between the surface emitting laser array 20 and each lead frame 9 so as to be positioned between the two. The wiring 21 is provided between the coating area A on the outer periphery of the surface emitting laser array 20 and each lead frame 9 so as to be close to each other in a non-contact state. In this way, the wiring 21 is provided on the outer periphery of the three sides excluding the light receiving element 4 side of the application region A.

(Inspection of mounting failure due to protrusion of conductive paste 5)
FIG. 6 is a diagram schematically showing the vicinity of the surface emitting laser array 20 on the package 2 in this embodiment. FIG. 6A shows the conductive paste 5 applied in the application region A. FIG. FIG. 6B shows a normal state, and FIG. 6B shows an abnormal time when the conductive paste 5 protrudes from the application region A. FIG.

  As shown in FIG. 6, each electrode pad on the surface emitting laser array 20 is electrically connected to the light emitting unit terminal 16 from each lead frame 9 on the package 2 connected via the bonding wire 11. The light emitting unit terminal 16 receives a write signal b from the write control unit 15 (see FIG. 3). The bottom surface of the surface emitting laser array 20 is electrically connected to the ground terminal (GND terminal) 17 via the conductive paste 5. The wiring 21 is electrically connected to the abnormality detection terminal 18. The light emitting unit terminal 16, the ground terminal 17, and the abnormality detection terminal 18 are provided on the end surface of the surface emitting laser module 1a.

  The abnormality detection terminal 18 is electrically connected to an inspection device 19 that determines an electrical state (open state (no load state) or ground potential state) of the abnormality detection terminal 18.

  6A, when the surface-emitting laser array 20 is mounted on the plane in the package 2 with the conductive paste 5, the conductive paste 5 protruding from the bottom surface of the surface-emitting laser array 20 is formed. When it does not protrude from the coating area A, that is, when the protruding conductive paste 5 is not in contact with the wiring 21, it is normal.

  Thus, at the normal time shown in FIG. 6A, the abnormality detection terminal 18 is in an open state (no load state). Therefore, when the inspection device 19 detects that the abnormality detection terminal 18 is in an open state, the protruding conductive paste 5 is in the application region A in a normal state (mounting of the surface emitting laser array 20 is in a normal state). For example, “normal” is displayed on the screen of a display device (not shown).

  In the surface emitting laser module 1a according to the present embodiment, the surface emitting laser array 20 and the light receiving element 4 are adjacent to each other, so that the coating region A for mounting the surface emitting laser array 20 in the package 2 with the conductive paste 5 is used. Is narrow.

  For this reason, as shown in FIG. 6B, when the surface emitting laser array 20 is mounted on the plane in the package 2 with the conductive paste 5, the conductive paste 5 protruding from the bottom surface of the surface emitting laser array 20. However, a mounting failure may occur that protrudes from the application area A to the lead frame 9 side (left and lower lead frame 9 sides in the figure). In FIG. 6B, the conductive paste 5 protrudes to the wiring 21, but when the amount of protrusion is larger, the protruding conductive paste 5 reaches each lead frame 9 on the outside.

  In this embodiment, since each lead frame 9 is located close to the outside of the wiring 21 as described above, the conductive paste 5 protrudes from the inside of the application region A to the lead frame 9 side, and the exposed conductive material. When the paste 5 is in contact with the wiring 21, it is regarded as abnormal. When the protruding conductive paste 5 is in contact with the wiring 21, it is highly likely that the protruding conductive paste 5 is in contact with the lead frame 9, and the surface emitting laser array 20 is in a poorly mounted state. .

  At the time of abnormality shown in FIG. 6B (at the time of mounting failure), since the protruding conductive paste 5 is in contact with the wiring 21, the abnormality detection terminal 18 is in the ground (GND) potential state. Therefore, when the inspection device 19 detects that the abnormality detection terminal 18 is in the ground potential state, the abnormal state (surface emitting laser array) in which the conductive paste 5 protrudes from the coating region A to the lead frame 9 side. For example, “Mounting failure” is displayed on the screen of a display device (not shown).

  As described above, when the surface emitting laser array 20 is mounted on the plane in the package 2 with the conductive paste 5 adjacent to the light receiving element 4, the space between the surface emitting laser array 20 and each lead frame 9. Mounting failure due to protrusion of the conductive paste 5 from the application area A by determining the electrical state (open state or ground potential state) of the abnormality detection terminal 18 electrically connected to the wiring 21 provided in Can be easily inspected.

  Conventionally, mounting defects due to protrusion of the conductive paste 5 do not occur with respect to each lead frame 9 (each light emitting portion terminal 16) provided according to a plurality of light emitting portions of the surface emitting laser array 20. When inspecting these, since all the light emitting part terminals 16 are inspected one by one in order by the inspection apparatus, it takes time for the inspection.

  On the other hand, in this embodiment, as described above, the electrical state of the abnormality detection terminal 18 electrically connected to the wiring 21 provided between the surface emitting laser array 20 and each lead frame 9 ( By determining the open state or the ground potential state), it is possible to determine whether the whole is normal (no mounting failure) or abnormal (mounting failure). Therefore, unlike the prior art, it is not necessary to inspect whether or not all the light emitting unit terminals 16 are defectively mounted one by one, and it is possible to inspect the surface emitting laser array 20 for mounting defects in a short time. .

<Embodiment 3>
FIG. 7 is a schematic plan view illustrating a configuration of a surface emitting laser module as an example of a semiconductor device according to the third embodiment.

  As shown in FIG. 7, in the surface emitting laser module 1 b according to this embodiment, the surface emitting laser elements 20 are arranged in an array, and the surface emitting laser array 20 having a structure having a plurality of light emitting units is adjacent to the light receiving element 4. Then, it is mounted on a plane in the package 2 via the conductive paste 5. A cap 8 having the transparent glass plate 7 shown in FIG. 1 is provided in front of the surface emitting laser array 20 and the light receiving element 4.

  A plurality of lead frames 9 are provided in the package 2 according to the number of light emitting portions of the surface emitting laser array 20 on the outer periphery in the four directions of the surface emitting laser array 20. The upper surface of the surface emitting laser array 20 and each lead frame 9 are electrically connected via bonding wires 11 such as gold wires.

  Between the surface emitting laser array 20 and each lead frame 9, wiring 22 is provided so as to surround the entire coating area A on the outer periphery of the surface emitting laser array 20. The wiring 22 is provided between the coating area A and each lead frame 9 so as to be close to each other in a non-contact state.

(Inspection of mounting failure due to protrusion of conductive paste 5)
FIG. 8 is a diagram schematically showing the vicinity of the surface emitting laser array 20 on the package 2 in this embodiment. FIG. 8A shows the conductive paste 5 applied in the application region A. FIG. FIG. 8B is a diagram showing a normal time, and FIG. 8B is a diagram showing an abnormal time when the conductive paste 5 protrudes from the application region A. FIG.

  As shown in FIG. 8, each pad portion on the surface emitting laser array 20 is electrically connected to the light emitting portion terminal 16 from each lead frame 9 on the package 2 connected via the bonding wire 11. The light emitting unit terminal 16 receives a write signal b from the write control unit 15 (see FIG. 3). The bottom surface of the surface emitting laser array 20 is electrically connected to the ground terminal (GND terminal) 17 via the conductive paste 5. The wiring 22 is electrically connected to the abnormality detection terminal 18. The light emitting unit terminal 16, the ground terminal 17, and the abnormality detection terminal 18 are provided on the end surface of the surface emitting laser module 1b.

  The abnormality detection terminal 18 is electrically connected to an inspection device 19 that determines an electrical state (open state (no load state) or ground potential state) of the abnormality detection terminal 18.

  8A, when the surface emitting laser array 20 is mounted on the plane in the package 2 with the conductive paste 5, the conductive paste 5 protruding from the bottom surface of the surface emitting laser array 20 is formed. When it does not protrude from the coating area A, that is, when the protruding conductive paste 5 is not in contact with the wiring 22, it is normal.

  Thus, at the normal time shown in FIG. 8A, the abnormality detection terminal 18 is in an open state (no load state). Therefore, when the inspection device 19 detects that the abnormality detection terminal 18 is in an open state, the protruding conductive paste 5 is in the application region A in a normal state (mounting of the surface emitting laser array 20 is in a normal state). For example, “normal” is displayed on the screen of a display device (not shown).

  In the surface emitting laser module 1b according to the present embodiment, the surface emitting laser array 20 and the light receiving element 4 are adjacent to each other, so that the coating region A for mounting the surface emitting laser array 20 with the conductive paste 5 in the package 2 is provided. Is narrow.

  For this reason, as shown in FIG. 8B, when the surface emitting laser array 20 is mounted on the plane in the package 2 with the conductive paste 5, the conductive paste 5 protruding from the bottom surface of the surface emitting laser array 20. However, a mounting failure may occur that protrudes from the application area A to the lead frame 9 side (left and lower lead frame 9 sides in the figure). In FIG. 8B, the conductive paste 5 protrudes to the wiring 22, but when the amount of protrusion is larger, the protruding conductive paste 5 reaches each lead frame 9 on the outside.

  In the present embodiment, since each lead frame 9 is located close to the outside of the wiring 22 as described above, the conductive paste 5 protrudes from the coating region A to the lead frame 9 side, and the exposed conductive material. When the paste 5 is in contact with the wiring 22, it is regarded as abnormal. When the protruding conductive paste 5 is in contact with the wiring 22, it is highly likely that the protruding conductive paste 5 is in contact with the lead frame 9, and the surface emitting laser array 20 is in a poorly mounted state. .

  At the time of abnormality shown in FIG. 8B (when mounting is defective), since the protruding conductive paste 5 is in contact with the wiring 22, the abnormality detection terminal 18 is in the ground (GND) potential state. Therefore, when the inspection device 19 detects that the abnormality detection terminal 18 is in the ground potential state, the abnormal state (surface emitting laser array) in which the conductive paste 5 protrudes from the coating region A to the lead frame 9 side. For example, “Mounting failure” is displayed on the screen of a display device (not shown).

  As described above, when the surface emitting laser array 20 is mounted on the plane in the package 2 with the conductive paste 5 adjacent to the light receiving element 4, the space between the surface emitting laser array 20 and each lead frame 9. By determining the electrical state (open state or ground potential state) of the abnormality detection terminal 18 that is electrically connected to the wiring 22 provided on the light emitting part terminal 16, it is possible to check each light emitting unit terminal 16 for a mounting failure. In addition, it is possible to easily inspect for mounting defects due to protrusion of the conductive paste 5 from the application region A.

  Furthermore, in this embodiment, since the wiring 22 is provided so as to surround the entire coating area A, even if the conductive paste 5 protrudes from the coating area A in any direction, the abnormal state (surface emitting laser array) 20 mounting failure states) can be detected.

  Also in the present embodiment, as in the second embodiment, the electrical state (open) of the abnormality detection terminal 18 that is electrically connected to the wiring 22 provided between the surface emitting laser array 20 and each lead frame 9. By determining the state or the ground potential state), it is possible to determine whether the whole is normal (no mounting failure) or abnormal (mounting failure). Therefore, unlike the prior art, it is not necessary to inspect whether or not all the light emitting unit terminals 16 are defectively mounted one by one, and it is possible to inspect the surface emitting laser array 20 for mounting defects in a short time. .

<Embodiment 4>
FIG. 9 is a schematic diagram illustrating a configuration of a laser printer as an example of an image forming apparatus including an optical scanning device according to the fourth embodiment. In addition to the laser printer, examples of the image forming apparatus include a copying machine, a printer, a facsimile machine, and a multifunction machine having these functions.

  As shown in FIG. 9, the laser printer 30 includes an optical scanning device 31, a photosensitive drum 32, a charger 33, a developing roller 34, a toner cartridge 35, a cleaning blade 36, a paper feed tray 37, a paper feed roller 38, a resist. A roller pair 39, a transfer roller 40, a static elimination unit 41, a fixing roller 42, a paper discharge roller 43, a paper discharge tray 44, and the like are provided.

  The charger 33, the developing roller 34, the transfer roller 40, the charge removal unit 41, and the cleaning blade 36 are arranged in the vicinity of the surface of the photosensitive drum 32 along the rotation direction (arrow direction) of the photosensitive drum 32.

  In the optical scanning device 31, the surface (surface to be scanned) of the photosensitive drum 32 as an image carrier charged by the charger 33 is modulated based on image information input from a host device 45 such as a personal computer. Scanning (writing exposure) is performed with the laser beam L, and a latent image corresponding to the image information is formed on the surface of the photosensitive drum 32. The latent image formed on the surface of the photosensitive drum 32 moves in the direction of the developing roller 34 as the photosensitive drum 32 rotates. Details of the optical scanning device 31 will be described later.

  The toner cartridge 35 stores toner, and this toner is supplied to the developing roller 34. The developing roller 34 causes the toner supplied from the toner cartridge 35 to adhere to the latent image formed on the surface of the photosensitive drum 32 to visualize the image information. The latent image (hereinafter referred to as “toner image”) to which the toner is attached in this manner moves in the direction of the transfer roller 40 as the photosensitive drum 32 rotates.

  At this time, the paper feed roller 38 feeds the recording paper P one by one from the paper feed tray 37 and conveys it to the registration roller pair 39. The registration roller pair 39 is disposed in the vicinity of the transfer roller 40, temporarily holds the recording paper P fed by the paper feeding roller 38, and aligns the recording paper P with the rotation of the photosensitive drum 32, so It is sent out toward the transfer nip between the drum 32 and the transfer roller 40.

  In order to electrically attract the toner on the surface of the photosensitive drum 32 to the recording paper P, a voltage having a polarity opposite to that of the toner is applied to the transfer roller 40. With this voltage, the toner image on the surface of the photosensitive drum 32 is transferred to the recording paper P. The recording paper P onto which the toner image has been transferred is sent to a fixing nip between the fixing roller 42 and the pressure roller 46.

  At the fixing nip between the fixing roller 42 and the pressure roller 46, heat and pressure are applied to the recording paper P, whereby the toner image is fixed on the recording paper P. The recording paper P on which the toner image is fixed is conveyed to a paper discharge tray 44 via a paper discharge roller 43.

  After the toner image is transferred and fixed, the surface of the photosensitive drum 32 is discharged by the discharging unit 41. Further, the toner (residual toner) remaining on the surface of the photosensitive drum 32 is removed by the cleaning blade 36.

  Next, the configuration of the optical scanning device 31 will be described. FIG. 10 is a diagram illustrating a configuration of the optical scanning device 31.

  As shown in FIG. 10, the optical scanning device 31 includes a light source unit 50, a coupling lens 51, an aperture 52, a cylindrical lens 53, a polygon mirror 54, an fθ lens 55, a toroidal lens 56, and two first and second mirrors. 57, 58, and a main controller (not shown) that controls the above-described units in an integrated manner.

  The light source unit 50 includes the surface emitting laser element or the surface emitting laser module according to any one of the above-described embodiments (for example, the surface emitting laser module 1a according to the second embodiment illustrated in FIG. 5).

  The coupling lens 51 shapes the light beam (laser light) L emitted from the light source unit 50 into substantially parallel light, and the aperture 52 defines the beam diameter of the light beam.

  The cylindrical lens 53 condenses the light beam that has passed through the aperture 52 on the reflection surface of the polygon mirror 54 via the first mirror 57.

  The polygon mirror 54 as the deflecting means is formed of a regular hexagonal columnar member having a low height, and six deflecting surfaces are formed on the side surface. And it is rotated at a constant angular velocity in the direction of the arrow by a rotation mechanism (not shown). Accordingly, the light beam emitted from the light source unit 50 and condensed on the deflection surface of the polygon mirror 54 by the cylindrical lens 53 is deflected at a constant angular velocity by the rotation of the polygon mirror 54.

  The fθ lens 55 has an image height proportional to the incident angle of the light beam from the polygon mirror 54, and moves the image surface of the light beam deflected by the polygon mirror 54 at a constant angular velocity at a constant speed in the main scanning direction. Let

  The toroidal lens 56 irradiates the surface of the photosensitive drum 32 (see FIG. 9) with the light beam from the fθ lens 55 via the second mirror 58, thereby forming a light spot on the surface of the photosensitive drum 32. This light spot moves in the longitudinal direction of the photosensitive drum 32 as the polygon mirror 54 rotates. That is, the surface of the photosensitive drum 32 is scanned. The moving direction of the light spot at this time is the main scanning direction. In the present embodiment, the scanning optical system is configured by the fθ lens 55, the toroidal lens 56 and the second mirror 58.

  The light source unit 50 includes, for example, the surface emitting laser module 1a) according to the second embodiment illustrated in FIG. 5, and the writing control unit 15 outputs the output monitor input from the light receiving element 4 as illustrated in FIG. Based on the signal a, the beam intensity of the laser light L emitted from the surface emitting laser array 20 is detected, and the detected beam intensity is compared with a reference value. Then, the injection current to the surface emitting laser array 20 is controlled so that the output of the laser light emitted from the surface emitting laser array 20 becomes a predetermined value. Based on this current control, a write signal (current signal) b is output to the surface emitting laser array 20. The value of the write signal b is held until the next detection of the beam intensity, and the beam intensity of the laser light L output from the surface emitting laser element 3 is kept constant.

  As described above, the laser printer 30 including the optical scanning device 31 of the present embodiment has the surface emitting laser element or the surface emitting laser module of any of the above embodiments in the light source unit 50 of the optical scanning device 31. doing. Therefore, a normal surface-emitting laser element or surface-emitting laser module that does not have mounting defects due to the protrusion of the conductive paste is incorporated in the light source unit 50. For this reason, scanning (writing) with a laser beam can be performed satisfactorily, and the laser printer 30 provided with the optical scanning device 31 can output a high-quality image (toner image).

  In the first to third embodiments described above, the surface emitting laser element (surface emitting laser array) and the light receiving element are adjacently mounted on one surface of the semiconductor package via the conductive paste. The present invention can be similarly applied to a semiconductor device in which a plurality of semiconductor chips other than these are adjacently mounted via a conductive paste.

DESCRIPTION OF SYMBOLS 1, 1a, 1b Surface emitting laser module 2 Package 3 Surface emitting laser element 4 Light receiving element 7 Transparent glass plate 9, 10 Lead frame 11, 12 Bonding wire 13, 14, 21, 22, Wiring 15 Write control part 16 Light emitting part terminal 17 Ground terminal 18 Anomaly detection terminal 19 Inspection device 20 Surface emitting laser array 30 Laser printer 31 Optical scanning device 32 Photosensitive drum 50 Light source unit 54 Polygon mirror A Coating area

JP 2013-51283 A

Claims (7)

A semiconductor device in which at least a first semiconductor chip and a second semiconductor chip are adjacently mounted on one surface of a semiconductor package via a conductive paste,
On the one surface, having a wiring provided so as to surround at least a part of the periphery of the conductive paste application region,
The wiring is electrically connected to an inspection terminal provided in the semiconductor device,
A semiconductor device, wherein the conductive paste is applied to the application region and at least the first semiconductor chip is mounted.   2. The semiconductor device according to claim 1, wherein the electrical state of the inspection terminal is either an open state or a ground potential state that is not electrically connected. A lead frame connected to at least the first semiconductor chip by a bonding wire is provided on at least one side of the conductive paste application region on the one surface,
The semiconductor device according to claim 1, wherein the wiring is provided so as to be located between a periphery of the conductive paste application region and the lead frame. A lead frame connected to at least the first semiconductor chip by a bonding wire is provided on the entire circumference of the conductive paste application region on the one surface,
The said wiring is provided so that it may be located between the circumference | surroundings of the said application | coating area | region and the said lead frame so that the whole application | coating area | region of the said conductive paste may be enclosed. Semiconductor device.   5. The semiconductor device according to claim 1, wherein the first semiconductor chip is a surface emitting laser array having a plurality of light emitting units. 6. An optical scanning device that scans a surface to be scanned with a light beam,
A light source unit comprising the semiconductor device according to claim 5;
Deflection means for deflecting the light beam output from the light source unit;
An optical scanning apparatus comprising: a scanning optical system that condenses the deflected light beams on the surface to be scanned. At least one image carrier;
An image forming apparatus comprising at least the optical scanning device according to claim 6, which scans the image carrier with a light beam including image information.